Add a CFX_XMLDocument class.

This CL adds a CFX_XMLDocument to act as the XML node container. All
nodes are now owned by the document and the document is returned by the
CFX_XMLParser.

Classes which parse XML files now store the document instead of the root
node.

BUG: chromium:835636
Change-Id: I1e07d6115cf14714911d6fd4c3fa920c94fd5faf
Reviewed-on: https://pdfium-review.googlesource.com/31313
Reviewed-by: Henrique Nakashima <hnakashima@chromium.org>
Commit-Queue: dsinclair <dsinclair@chromium.org>

21 files changed, 518 insertions, 471 deletions

diff --git a/core/fxcrt/xml/cfx_xmlchardata.cpp b/core/fxcrt/xml/cfx_xmlchardata.cpp
index e62a43ac53..307d319537 100644
--- a/core/fxcrt/xml/cfx_xmlchardata.cpp
+++ b/core/fxcrt/xml/cfx_xmlchardata.cpp
@@ -6,6 +6,7 @@
 
 #include "core/fxcrt/xml/cfx_xmlchardata.h"
 
+#include "core/fxcrt/xml/cfx_xmldocument.h"
 #include "third_party/base/ptr_util.h"
 
 CFX_XMLCharData::CFX_XMLCharData(const WideString& wsCData)
@@ -17,8 +18,8 @@ FX_XMLNODETYPE CFX_XMLCharData::GetType() const {
   return FX_XMLNODE_CharData;
 }
 
-std::unique_ptr<CFX_XMLNode> CFX_XMLCharData::Clone() {
-  return pdfium::MakeUnique<CFX_XMLCharData>(GetText());
+CFX_XMLNode* CFX_XMLCharData::Clone(CFX_XMLDocument* doc) {
+  return doc->CreateNode<CFX_XMLCharData>(GetText());
 }
 
 void CFX_XMLCharData::Save(
diff --git a/core/fxcrt/xml/cfx_xmlchardata.h b/core/fxcrt/xml/cfx_xmlchardata.h
index 0cdc348f26..013414bc82 100644
--- a/core/fxcrt/xml/cfx_xmlchardata.h
+++ b/core/fxcrt/xml/cfx_xmlchardata.h
@@ -12,6 +12,8 @@
 #include "core/fxcrt/fx_string.h"
 #include "core/fxcrt/xml/cfx_xmltext.h"
 
+class CFX_XMLDocument;
+
 class CFX_XMLCharData : public CFX_XMLText {
  public:
   explicit CFX_XMLCharData(const WideString& wsCData);
@@ -19,7 +21,7 @@ class CFX_XMLCharData : public CFX_XMLText {
 
   // CFX_XMLNode
   FX_XMLNODETYPE GetType() const override;
-  std::unique_ptr<CFX_XMLNode> Clone() override;
+  CFX_XMLNode* Clone(CFX_XMLDocument* doc) override;
   void Save(const RetainPtr<IFX_SeekableWriteStream>& pXMLStream) override;
 };
 
diff --git a/core/fxcrt/xml/cfx_xmlchardata_unittest.cpp b/core/fxcrt/xml/cfx_xmlchardata_unittest.cpp
index 0fa48e520f..4f0c49eaac 100644
--- a/core/fxcrt/xml/cfx_xmlchardata_unittest.cpp
+++ b/core/fxcrt/xml/cfx_xmlchardata_unittest.cpp
@@ -3,6 +3,7 @@
 // found in the LICENSE file.
 
 #include "core/fxcrt/xml/cfx_xmlchardata.h"
+#include "core/fxcrt/xml/cfx_xmldocument.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "testing/string_write_stream.h"
 #include "testing/test_support.h"
@@ -18,12 +19,14 @@ TEST(CFX_XMLCharDataTest, GetText) {
 }
 
 TEST(CFX_XMLCharDataTest, Clone) {
+  CFX_XMLDocument doc;
+
   CFX_XMLCharData data(L"My Data");
-  auto clone = data.Clone();
+  CFX_XMLNode* clone = data.Clone(&doc);
   EXPECT_TRUE(clone != nullptr);
-  EXPECT_NE(&data, clone.get());
+  EXPECT_NE(&data, clone);
   ASSERT_EQ(FX_XMLNODE_CharData, clone->GetType());
-  EXPECT_EQ(L"My Data", static_cast<CFX_XMLCharData*>(clone.get())->GetText());
+  EXPECT_EQ(L"My Data", static_cast<CFX_XMLCharData*>(clone)->GetText());
 }
 
 TEST(CFX_XMLCharDataTest, Save) {
diff --git a/core/fxcrt/xml/cfx_xmldocument.cpp b/core/fxcrt/xml/cfx_xmldocument.cpp
new file mode 100644
index 0000000000..f6e55551ed
--- /dev/null
+++ b/core/fxcrt/xml/cfx_xmldocument.cpp
@@ -0,0 +1,14 @@
+// Copyright 2018 PDFium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "core/fxcrt/xml/cfx_xmldocument.h"
+#include "core/fxcrt/fx_system.h"
+#include "core/fxcrt/xml/cfx_xmlinstruction.h"
+#include "third_party/base/ptr_util.h"
+
+CFX_XMLDocument::CFX_XMLDocument() {
+  root_ = CreateNode<CFX_XMLElement>(L"root");
+}
+
+CFX_XMLDocument::~CFX_XMLDocument() = default;
diff --git a/core/fxcrt/xml/cfx_xmldocument.h b/core/fxcrt/xml/cfx_xmldocument.h
new file mode 100644
index 0000000000..a568f8390f
--- /dev/null
+++ b/core/fxcrt/xml/cfx_xmldocument.h
@@ -0,0 +1,37 @@
+// Copyright 2018 PDFium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef CORE_FXCRT_XML_CFX_XMLDOCUMENT_H_
+#define CORE_FXCRT_XML_CFX_XMLDOCUMENT_H_
+
+#include <memory>
+#include <utility>
+#include <vector>
+
+#include "core/fxcrt/unowned_ptr.h"
+#include "core/fxcrt/xml/cfx_xmlelement.h"
+#include "third_party/base/ptr_util.h"
+
+class CFX_XMLInstruction;
+class CFX_XMLNode;
+
+class CFX_XMLDocument {
+ public:
+  CFX_XMLDocument();
+  ~CFX_XMLDocument();
+
+  CFX_XMLElement* GetRoot() const { return root_.Get(); }
+
+  template <typename T, typename... Args>
+  T* CreateNode(Args&&... args) {
+    nodes_.push_back(pdfium::MakeUnique<T>(std::forward<Args>(args)...));
+    return static_cast<T*>(nodes_.back().get());
+  }
+
+ private:
+  std::vector<std::unique_ptr<CFX_XMLNode>> nodes_;
+  UnownedPtr<CFX_XMLElement> root_;
+};
+
+#endif  // CORE_FXCRT_XML_CFX_XMLDOCUMENT_H_
diff --git a/core/fxcrt/xml/cfx_xmldocument_unittest.cpp b/core/fxcrt/xml/cfx_xmldocument_unittest.cpp
new file mode 100644
index 0000000000..486b040db5
--- /dev/null
+++ b/core/fxcrt/xml/cfx_xmldocument_unittest.cpp
@@ -0,0 +1,22 @@
+// Copyright 2018 PDFium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "core/fxcrt/xml/cfx_xmldocument.h"
+#include "core/fxcrt/xml/cfx_xmlelement.h"
+#include "core/fxcrt/xml/cfx_xmlinstruction.h"
+#include "testing/gtest/include/gtest/gtest.h"
+#include "testing/test_support.h"
+
+TEST(CFX_XMLDocumentTest, Root) {
+  CFX_XMLDocument doc;
+  EXPECT_TRUE(doc.GetRoot() != nullptr);
+}
+
+TEST(CFX_XMLDocumentTest, CreateNode) {
+  CFX_XMLDocument doc;
+  auto* node = doc.CreateNode<CFX_XMLElement>(L"elem");
+
+  ASSERT_EQ(FX_XMLNODE_Element, node->GetType());
+  EXPECT_EQ(L"elem", node->GetName());
+}
diff --git a/core/fxcrt/xml/cfx_xmlelement.cpp b/core/fxcrt/xml/cfx_xmlelement.cpp
index 3befb242c9..74351b8c58 100644
--- a/core/fxcrt/xml/cfx_xmlelement.cpp
+++ b/core/fxcrt/xml/cfx_xmlelement.cpp
@@ -11,6 +11,7 @@
 #include "core/fxcrt/cfx_widetextbuf.h"
 #include "core/fxcrt/fx_extension.h"
 #include "core/fxcrt/xml/cfx_xmlchardata.h"
+#include "core/fxcrt/xml/cfx_xmldocument.h"
 #include "core/fxcrt/xml/cfx_xmltext.h"
 #include "third_party/base/ptr_util.h"
 #include "third_party/base/stl_util.h"
@@ -26,20 +27,18 @@ FX_XMLNODETYPE CFX_XMLElement::GetType() const {
   return FX_XMLNODE_Element;
 }
 
-std::unique_ptr<CFX_XMLNode> CFX_XMLElement::Clone() {
-  auto pClone = pdfium::MakeUnique<CFX_XMLElement>(name_);
-  pClone->attrs_ = attrs_;
+CFX_XMLNode* CFX_XMLElement::Clone(CFX_XMLDocument* doc) {
+  auto* node = doc->CreateNode<CFX_XMLElement>(name_);
+  node->attrs_ = attrs_;
 
-  // TODO(dsinclair): This clone is wrong. It doesn't clone child nodes just
-  // copies text nodes?
-  WideString wsText;
+  // TODO(dsinclair): This clone is wrong. It doesn't clone all child nodes just
+  // text nodes?
   for (CFX_XMLNode* pChild = GetFirstChild(); pChild;
        pChild = pChild->GetNextSibling()) {
     if (pChild->GetType() == FX_XMLNODE_Text)
-      wsText += static_cast<CFX_XMLText*>(pChild)->GetText();
+      node->AppendChild(pChild->Clone(doc));
   }
-  pClone->SetTextData(wsText);
-  return std::move(pClone);
+  return node;
 }
 
 WideString CFX_XMLElement::GetLocalTagName() const {
@@ -60,7 +59,6 @@ WideString CFX_XMLElement::GetNamespaceURI() const {
     attr += L":";
     attr += wsPrefix;
   }
-
   const CFX_XMLNode* pNode = this;
   while (pNode) {
     if (pNode->GetType() != FX_XMLNODE_Element)
@@ -89,13 +87,6 @@ WideString CFX_XMLElement::GetTextData() const {
   return buffer.MakeString();
 }
 
-void CFX_XMLElement::SetTextData(const WideString& wsText) {
-  // TODO(dsinclair): Shouldn't this remove the children if you set blank text?
-  if (wsText.IsEmpty())
-    return;
-  AppendChild(pdfium::MakeUnique<CFX_XMLText>(wsText));
-}
-
 void CFX_XMLElement::Save(
     const RetainPtr<IFX_SeekableWriteStream>& pXMLStream) {
   ByteString bsNameEncoded = name_.UTF8Encode();
diff --git a/core/fxcrt/xml/cfx_xmlelement.h b/core/fxcrt/xml/cfx_xmlelement.h
index 678ba6d996..ca5fd5e797 100644
--- a/core/fxcrt/xml/cfx_xmlelement.h
+++ b/core/fxcrt/xml/cfx_xmlelement.h
@@ -14,6 +14,8 @@
 #include "core/fxcrt/fx_string.h"
 #include "core/fxcrt/xml/cfx_xmlnode.h"
 
+class CFX_XMLDocument;
+
 class CFX_XMLElement : public CFX_XMLNode {
  public:
   explicit CFX_XMLElement(const WideString& wsTag);
@@ -21,7 +23,7 @@ class CFX_XMLElement : public CFX_XMLNode {
 
   // CFX_XMLNode
   FX_XMLNODETYPE GetType() const override;
-  std::unique_ptr<CFX_XMLNode> Clone() override;
+  CFX_XMLNode* Clone(CFX_XMLDocument* doc) override;
   void Save(const RetainPtr<IFX_SeekableWriteStream>& pXMLStream) override;
 
   WideString GetName() const { return name_; }
@@ -44,7 +46,6 @@ class CFX_XMLElement : public CFX_XMLNode {
   WideString GetNamespaceURI() const;
 
   WideString GetTextData() const;
-  void SetTextData(const WideString& wsText);
 
  private:
   WideString AttributeToString(const WideString& name, const WideString& value);
diff --git a/core/fxcrt/xml/cfx_xmlelement_unittest.cpp b/core/fxcrt/xml/cfx_xmlelement_unittest.cpp
index 79e067f511..1e53ef3dd7 100644
--- a/core/fxcrt/xml/cfx_xmlelement_unittest.cpp
+++ b/core/fxcrt/xml/cfx_xmlelement_unittest.cpp
@@ -2,15 +2,13 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#include <utility>
-
-#include "core/fxcrt/xml/cfx_xmlchardata.h"
 #include "core/fxcrt/xml/cfx_xmlelement.h"
+#include "core/fxcrt/xml/cfx_xmlchardata.h"
+#include "core/fxcrt/xml/cfx_xmldocument.h"
 #include "core/fxcrt/xml/cfx_xmltext.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "testing/string_write_stream.h"
 #include "testing/test_support.h"
-#include "third_party/base/ptr_util.h"
 
 TEST(CFX_XMLElementTest, GetType) {
   CFX_XMLElement node(L"node");
@@ -74,19 +72,24 @@ TEST(CFX_XMLElementTest, Attributes) {
 }
 
 TEST(CFX_XMLElementTest, Clone) {
+  CFX_XMLDocument doc;
+
   CFX_XMLElement node(L"test:node");
   node.SetAttribute(L"first", L"one");
   node.SetAttribute(L"second", L"two");
   node.SetAttribute(L"xmlns:test", L"https://example.org/test");
 
-  node.AppendChild(pdfium::MakeUnique<CFX_XMLText>(L"Text Child"));
-  node.AppendChild(pdfium::MakeUnique<CFX_XMLElement>(L"Node child"));
+  CFX_XMLText text_child1(L"Text Child");
+  node.AppendChild(&text_child1);
 
-  auto clone = node.Clone();
+  CFX_XMLElement node_child1(L"Node child");
+  node.AppendChild(&node_child1);
+
+  CFX_XMLNode* clone = node.Clone(&doc);
   EXPECT_TRUE(clone != nullptr);
 
   ASSERT_EQ(FX_XMLNODE_Element, clone->GetType());
-  CFX_XMLElement* inst = static_cast<CFX_XMLElement*>(clone.get());
+  CFX_XMLElement* inst = static_cast<CFX_XMLElement*>(clone);
 
   EXPECT_EQ(L"test:node", inst->GetName());
   EXPECT_EQ(L"node", inst->GetLocalTagName());
@@ -129,14 +132,17 @@ TEST(CFX_XMLElementTest, SaveWithChildren) {
   auto stream = pdfium::MakeRetain<StringWriteStream>();
   CFX_XMLElement node(L"node");
 
-  node.AppendChild(pdfium::MakeUnique<CFX_XMLText>(L"Text Child 1"));
+  CFX_XMLText text_child1(L"Text Child 1");
+  node.AppendChild(&text_child1);
+
+  CFX_XMLElement node_child1(L"node-child");
+  node.AppendChild(&node_child1);
 
-  auto child = pdfium::MakeUnique<CFX_XMLElement>(L"node-child");
-  CFX_XMLElement* node_child1 = child.get();
-  node.AppendChild(std::move(child));
+  CFX_XMLText text_child2(L"Text Child 2");
+  node_child1.AppendChild(&text_child2);
 
-  node_child1->AppendChild(pdfium::MakeUnique<CFX_XMLText>(L"Text Child 2"));
-  node.AppendChild(pdfium::MakeUnique<CFX_XMLCharData>(L"Char Data"));
+  CFX_XMLCharData char_data1(L"Char Data");
+  node.AppendChild(&char_data1);
 
   node.Save(stream);
   EXPECT_EQ(
@@ -160,18 +166,18 @@ TEST(CFX_XMLElementTest, SaveWithNamespace) {
 
 TEST(CFX_XMLElementTest, GetFirstChildNamed) {
   CFX_XMLElement node(L"node");
-  auto child = pdfium::MakeUnique<CFX_XMLElement>(L"node-child");
-  CFX_XMLElement* node_child1 = child.get();
-  node.AppendChild(std::move(child));
+  CFX_XMLElement node_child1(L"node-child");
+  node.AppendChild(&node_child1);
 
   auto* found = node.GetFirstChildNamed(L"node-child");
   EXPECT_TRUE(found != nullptr);
-  EXPECT_EQ(node_child1, found);
+  EXPECT_EQ(&node_child1, found);
 }
 
 TEST(CFX_XMLElementTest, GetFirstChildNamedMissing) {
   CFX_XMLElement node(L"node");
-  node.AppendChild(pdfium::MakeUnique<CFX_XMLElement>(L"node-child"));
+  CFX_XMLElement node_child1(L"node-child");
+  node.AppendChild(&node_child1);
 
   auto* found = node.GetFirstChildNamed(L"node-sibling");
   EXPECT_TRUE(found == nullptr);
@@ -179,23 +185,26 @@ TEST(CFX_XMLElementTest, GetFirstChildNamedMissing) {
 
 TEST(CFX_XMLElementTest, GetNthChildNamed) {
   CFX_XMLElement node(L"node");
-  node.AppendChild(pdfium::MakeUnique<CFX_XMLElement>(L"node-child"));
-  node.AppendChild(pdfium::MakeUnique<CFX_XMLElement>(L"node-child"));
-
-  auto child = pdfium::MakeUnique<CFX_XMLElement>(L"node-child");
-  CFX_XMLElement* node_child3 = child.get();
-  node.AppendChild(std::move(child));
+  CFX_XMLElement node_child1(L"node-child");
+  CFX_XMLElement node_child2(L"node-child");
+  CFX_XMLElement node_child3(L"node-child");
+  node.AppendChild(&node_child1);
+  node.AppendChild(&node_child2);
+  node.AppendChild(&node_child3);
 
   auto* found = node.GetNthChildNamed(L"node-child", 2);
   EXPECT_TRUE(found != nullptr);
-  EXPECT_EQ(node_child3, found);
+  EXPECT_EQ(&node_child3, found);
 }
 
 TEST(CFX_XMLElementTest, GetNthChildNamedMissingChild) {
   CFX_XMLElement node(L"node");
-  node.AppendChild(pdfium::MakeUnique<CFX_XMLElement>(L"node-child"));
-  node.AppendChild(pdfium::MakeUnique<CFX_XMLElement>(L"node-child"));
-  node.AppendChild(pdfium::MakeUnique<CFX_XMLElement>(L"node-child"));
+  CFX_XMLElement node_child1(L"node-child");
+  CFX_XMLElement node_child2(L"node-child");
+  CFX_XMLElement node_child3(L"node-child");
+  node.AppendChild(&node_child1);
+  node.AppendChild(&node_child2);
+  node.AppendChild(&node_child3);
 
   auto* found = node.GetNthChildNamed(L"node-child", 5);
   EXPECT_TRUE(found == nullptr);
@@ -203,15 +212,18 @@ TEST(CFX_XMLElementTest, GetNthChildNamedMissingChild) {
 
 TEST(CFX_XMLElementTest, GetTextData) {
   CFX_XMLElement node(L"node");
-  node.AppendChild(pdfium::MakeUnique<CFX_XMLText>(L"Text Child 1"));
 
-  auto child = pdfium::MakeUnique<CFX_XMLElement>(L"Node child");
-  CFX_XMLElement* node_child1 = child.get();
-  node.AppendChild(std::move(child));
+  CFX_XMLText text_child1(L"Text Child 1");
+  node.AppendChild(&text_child1);
+
+  CFX_XMLElement node_child1(L"Node child");
+  node.AppendChild(&node_child1);
 
-  node_child1->AppendChild(pdfium::MakeUnique<CFX_XMLText>(L"Text Child 2"));
+  CFX_XMLText text_child2(L"Text Child 2");
+  node_child1.AppendChild(&text_child2);
 
-  node.AppendChild(pdfium::MakeUnique<CFX_XMLCharData>(L"Char Data"));
+  CFX_XMLCharData char_data1(L"Char Data");
+  node.AppendChild(&char_data1);
 
   EXPECT_EQ(L"Text Child 1Char Data", node.GetTextData());
 }
diff --git a/core/fxcrt/xml/cfx_xmlinstruction.cpp b/core/fxcrt/xml/cfx_xmlinstruction.cpp
index b7a87b588a..32841fb68e 100644
--- a/core/fxcrt/xml/cfx_xmlinstruction.cpp
+++ b/core/fxcrt/xml/cfx_xmlinstruction.cpp
@@ -10,6 +10,7 @@
 
 #include "core/fxcrt/fx_codepage.h"
 #include "core/fxcrt/fx_extension.h"
+#include "core/fxcrt/xml/cfx_xmldocument.h"
 #include "third_party/base/ptr_util.h"
 #include "third_party/base/stl_util.h"
 
@@ -22,10 +23,10 @@ FX_XMLNODETYPE CFX_XMLInstruction::GetType() const {
   return FX_XMLNODE_Instruction;
 }
 
-std::unique_ptr<CFX_XMLNode> CFX_XMLInstruction::Clone() {
-  auto pClone = pdfium::MakeUnique<CFX_XMLInstruction>(name_);
-  pClone->m_TargetData = m_TargetData;
-  return std::move(pClone);
+CFX_XMLNode* CFX_XMLInstruction::Clone(CFX_XMLDocument* doc) {
+  auto* node = doc->CreateNode<CFX_XMLInstruction>(name_);
+  node->m_TargetData = m_TargetData;
+  return node;
 }
 
 void CFX_XMLInstruction::AppendData(const WideString& wsData) {
diff --git a/core/fxcrt/xml/cfx_xmlinstruction.h b/core/fxcrt/xml/cfx_xmlinstruction.h
index 3be9d48573..153ef2b625 100644
--- a/core/fxcrt/xml/cfx_xmlinstruction.h
+++ b/core/fxcrt/xml/cfx_xmlinstruction.h
@@ -13,6 +13,8 @@
 #include "core/fxcrt/fx_string.h"
 #include "core/fxcrt/xml/cfx_xmlnode.h"
 
+class CFX_XMLDocument;
+
 class CFX_XMLInstruction : public CFX_XMLNode {
  public:
   explicit CFX_XMLInstruction(const WideString& wsTarget);
@@ -20,7 +22,7 @@ class CFX_XMLInstruction : public CFX_XMLNode {
 
   // CFX_XMLNode
   FX_XMLNODETYPE GetType() const override;
-  std::unique_ptr<CFX_XMLNode> Clone() override;
+  CFX_XMLNode* Clone(CFX_XMLDocument* doc) override;
   void Save(const RetainPtr<IFX_SeekableWriteStream>& pXMLStream) override;
 
   bool IsOriginalXFAVersion() const;
diff --git a/core/fxcrt/xml/cfx_xmlinstruction_unittest.cpp b/core/fxcrt/xml/cfx_xmlinstruction_unittest.cpp
index c60d401303..0c43c59ccd 100644
--- a/core/fxcrt/xml/cfx_xmlinstruction_unittest.cpp
+++ b/core/fxcrt/xml/cfx_xmlinstruction_unittest.cpp
@@ -4,6 +4,7 @@
 
 #include "core/fxcrt/xml/cfx_xmlinstruction.h"
 #include "core/fxcrt/cfx_memorystream.h"
+#include "core/fxcrt/xml/cfx_xmldocument.h"
 #include "core/fxcrt/xml/cfx_xmlelement.h"
 #include "core/fxcrt/xml/cfx_xmlparser.h"
 #include "testing/gtest/include/gtest/gtest.h"
@@ -41,15 +42,17 @@ TEST(CFX_XMLInstructionTest, TargetData) {
 }
 
 TEST(CFX_XMLInstructionTest, Clone) {
+  CFX_XMLDocument doc;
+
   CFX_XMLInstruction node(L"acrobat");
   node.AppendData(L"firstString");
   node.AppendData(L"secondString");
 
-  auto clone = node.Clone();
+  CFX_XMLNode* clone = node.Clone(&doc);
   EXPECT_TRUE(clone != nullptr);
 
   ASSERT_EQ(FX_XMLNODE_Instruction, clone->GetType());
-  CFX_XMLInstruction* inst = static_cast<CFX_XMLInstruction*>(clone.get());
+  CFX_XMLInstruction* inst = static_cast<CFX_XMLInstruction*>(clone);
 
   EXPECT_TRUE(inst->IsAcrobat());
 
@@ -87,14 +90,16 @@ TEST(CFX_XMLInstructionTest, ParseAndReSave) {
       reinterpret_cast<uint8_t*>(const_cast<char*>(input)), strlen(input),
       false);
 
-  CFX_XMLElement root(L"root");
-  CFX_XMLParser parser(&root, in_stream);
-  ASSERT_TRUE(parser.Parse());
-  ASSERT_TRUE(root.GetFirstChild() != nullptr);
-  ASSERT_EQ(FX_XMLNODE_Instruction, root.GetFirstChild()->GetType());
+  CFX_XMLParser parser(in_stream);
+  std::unique_ptr<CFX_XMLDocument> doc = parser.Parse();
+  ASSERT_TRUE(doc != nullptr);
+
+  CFX_XMLElement* root = doc->GetRoot();
+  ASSERT_TRUE(root->GetFirstChild() != nullptr);
+  ASSERT_EQ(FX_XMLNODE_Instruction, root->GetFirstChild()->GetType());
 
   CFX_XMLInstruction* node =
-      static_cast<CFX_XMLInstruction*>(root.GetFirstChild());
+      static_cast<CFX_XMLInstruction*>(root->GetFirstChild());
   ASSERT_TRUE(node != nullptr);
   EXPECT_TRUE(node->IsAcrobat());
 
@@ -109,3 +114,49 @@ TEST(CFX_XMLInstructionTest, ParseAndReSave) {
       "<?acrobat http://www.xfa.org/schema/xfa-template/3.3/ Display:1 ?>\n",
       out_stream->ToString());
 }
+
+TEST(CFX_XMLInstructionTest, ParseAndReSaveInnerInstruction) {
+  const char* input =
+      "<node>\n"
+      "<?acrobat http://www.xfa.org/schema/xfa-template/3.3/ Display:1 ?>\n"
+      "</node>";
+
+  auto in_stream = pdfium::MakeRetain<CFX_MemoryStream>(
+      reinterpret_cast<uint8_t*>(const_cast<char*>(input)), strlen(input),
+      false);
+
+  CFX_XMLParser parser(in_stream);
+  std::unique_ptr<CFX_XMLDocument> doc = parser.Parse();
+  ASSERT_TRUE(doc != nullptr);
+
+  CFX_XMLElement* root = doc->GetRoot();
+  ASSERT_TRUE(root->GetFirstChild() != nullptr);
+  ASSERT_TRUE(root->GetFirstChild()->GetType() == FX_XMLNODE_Element);
+
+  CFX_XMLElement* node = static_cast<CFX_XMLElement*>(root->GetFirstChild());
+  EXPECT_EQ(L"node", node->GetName());
+
+  CFX_XMLInstruction* instruction = nullptr;
+  for (auto* elem = node->GetFirstChild(); elem;
+       elem = elem->GetNextSibling()) {
+    if (elem->GetType() == FX_XMLNODE_Instruction) {
+      instruction = static_cast<CFX_XMLInstruction*>(elem);
+      break;
+    }
+  }
+  ASSERT_TRUE(instruction != nullptr);
+  EXPECT_TRUE(instruction->IsAcrobat());
+
+  auto& data = instruction->GetTargetData();
+  ASSERT_EQ(2U, data.size());
+  EXPECT_EQ(L"http://www.xfa.org/schema/xfa-template/3.3/", data[0]);
+  EXPECT_EQ(L"Display:1", data[1]);
+
+  auto out_stream = pdfium::MakeRetain<StringWriteStream>();
+  node->Save(out_stream);
+  EXPECT_EQ(
+      "<node>\n\n"
+      "<?acrobat http://www.xfa.org/schema/xfa-template/3.3/ Display:1 ?>\n\n"
+      "</node>\n",
+      out_stream->ToString());
+}
diff --git a/core/fxcrt/xml/cfx_xmlnode.cpp b/core/fxcrt/xml/cfx_xmlnode.cpp
index 088cbf367c..c8fea23bda 100644
--- a/core/fxcrt/xml/cfx_xmlnode.cpp
+++ b/core/fxcrt/xml/cfx_xmlnode.cpp
@@ -17,38 +17,26 @@
 
 CFX_XMLNode::CFX_XMLNode() = default;
 
-CFX_XMLNode::~CFX_XMLNode() {
-  DeleteChildren();
-}
+CFX_XMLNode::~CFX_XMLNode() = default;
 
 void CFX_XMLNode::DeleteChildren() {
-  CFX_XMLNode* child = last_child_.Get();
-  // Clear last child early as it will have been deleted already.
-  last_child_ = nullptr;
-  while (child) {
-    child = child->prev_sibling_.Get();
-    if (child) {
-      if (child->next_sibling_) {
-        child->next_sibling_->prev_sibling_ = nullptr;
-        child->next_sibling_->parent_ = nullptr;
-      }
-
-      child->next_sibling_ = nullptr;
-    }
-  }
-  if (first_child_) {
-    first_child_->next_sibling_ = nullptr;
+  while (first_child_) {
     first_child_->parent_ = nullptr;
+    first_child_->prev_sibling_ = nullptr;
+
+    CFX_XMLNode* child = first_child_;
+    first_child_ = child->next_sibling_;
+
+    child->next_sibling_ = nullptr;
   }
-  first_child_ = nullptr;
+  last_child_ = nullptr;
 }
 
-void CFX_XMLNode::AppendChild(std::unique_ptr<CFX_XMLNode> pNode) {
-  InsertChildNode(std::move(pNode), -1);
+void CFX_XMLNode::AppendChild(CFX_XMLNode* pNode) {
+  InsertChildNode(pNode, -1);
 }
 
-void CFX_XMLNode::InsertChildNode(std::unique_ptr<CFX_XMLNode> pNode,
-                                  int32_t index) {
+void CFX_XMLNode::InsertChildNode(CFX_XMLNode* pNode, int32_t index) {
   ASSERT(!pNode->parent_);
 
   pNode->parent_ = this;
@@ -56,36 +44,36 @@ void CFX_XMLNode::InsertChildNode(std::unique_ptr<CFX_XMLNode> pNode,
   if (!first_child_) {
     ASSERT(!last_child_);
 
-    first_child_ = std::move(pNode);
-    last_child_ = first_child_.get();
+    first_child_ = pNode;
+    last_child_ = first_child_;
     first_child_->prev_sibling_ = nullptr;
     first_child_->next_sibling_ = nullptr;
     return;
   }
 
   if (index == 0) {
-    first_child_->prev_sibling_ = pNode.get();
-    pNode->next_sibling_ = std::move(first_child_);
+    first_child_->prev_sibling_ = pNode;
+    pNode->next_sibling_ = first_child_;
     pNode->prev_sibling_ = nullptr;
-    first_child_ = std::move(pNode);
+    first_child_ = pNode;
     return;
   }
 
   int32_t iCount = 0;
-  CFX_XMLNode* pFind = first_child_.get();
+  CFX_XMLNode* pFind = first_child_;
   // Note, negative indexes, and indexes after the end of the list will result
   // in appending to the list.
   while (++iCount != index && pFind->next_sibling_)
-    pFind = pFind->next_sibling_.get();
+    pFind = pFind->next_sibling_;
 
   pNode->prev_sibling_ = pFind;
   if (pFind->next_sibling_)
-    pFind->next_sibling_->prev_sibling_ = pNode.get();
-  pNode->next_sibling_ = std::move(pFind->next_sibling_);
+    pFind->next_sibling_->prev_sibling_ = pNode;
+  pNode->next_sibling_ = pFind->next_sibling_;
 
-  pFind->next_sibling_ = std::move(pNode);
-  if (pFind == last_child_.Get())
-    last_child_ = pFind->next_sibling_.get();
+  pFind->next_sibling_ = pNode;
+  if (pFind == last_child_)
+    last_child_ = pFind->next_sibling_;
 }
 
 void CFX_XMLNode::RemoveChildNode(CFX_XMLNode* pNode) {
@@ -95,35 +83,25 @@ void CFX_XMLNode::RemoveChildNode(CFX_XMLNode* pNode) {
   if (pNode->GetParent() != this)
     return;
 
-  if (first_child_.get() == pNode) {
-    first_child_.release();
-    first_child_ = std::move(pNode->next_sibling_);
-    if (first_child_) {
-      first_child_->prev_sibling_ = nullptr;
-
-      if (first_child_->next_sibling_)
-        first_child_->next_sibling_->prev_sibling_ = first_child_.get();
-    }
-  } else {
-    CFX_XMLNode* prev = pNode->prev_sibling_.Get();
-    prev->next_sibling_.release();  // Release pNode
-    prev->next_sibling_ = std::move(pNode->next_sibling_);
-
-    if (prev->next_sibling_)
-      prev->next_sibling_->prev_sibling_ = prev;
-  }
+  if (first_child_ == pNode)
+    first_child_ = pNode->next_sibling_;
+  if (last_child_ == pNode)
+    last_child_ = pNode->prev_sibling_;
 
-  if (last_child_.Get() == pNode)
-    last_child_ = pNode->prev_sibling_.Get();
+  if (pNode->prev_sibling_)
+    pNode->prev_sibling_->next_sibling_ = pNode->next_sibling_;
+  if (pNode->next_sibling_)
+    pNode->next_sibling_->prev_sibling_ = pNode->prev_sibling_;
 
   pNode->parent_ = nullptr;
   pNode->prev_sibling_ = nullptr;
+  pNode->next_sibling_ = nullptr;
 }
 
 CFX_XMLNode* CFX_XMLNode::GetRoot() {
   CFX_XMLNode* pParent = this;
   while (pParent->parent_)
-    pParent = pParent->parent_.Get();
+    pParent = pParent->parent_;
 
   return pParent;
 }
diff --git a/core/fxcrt/xml/cfx_xmlnode.h b/core/fxcrt/xml/cfx_xmlnode.h
index 4c98a3b51a..95dc0acce9 100644
--- a/core/fxcrt/xml/cfx_xmlnode.h
+++ b/core/fxcrt/xml/cfx_xmlnode.h
@@ -19,39 +19,41 @@ enum FX_XMLNODETYPE {
   FX_XMLNODE_CharData,
 };
 
+class CFX_XMLDocument;
+
 class CFX_XMLNode {
  public:
   CFX_XMLNode();
   virtual ~CFX_XMLNode();
 
   virtual FX_XMLNODETYPE GetType() const = 0;
-  virtual std::unique_ptr<CFX_XMLNode> Clone() = 0;
+  virtual CFX_XMLNode* Clone(CFX_XMLDocument* doc) = 0;
   virtual void Save(const RetainPtr<IFX_SeekableWriteStream>& pXMLStream) = 0;
 
   CFX_XMLNode* GetRoot();
-  CFX_XMLNode* GetParent() const { return parent_.Get(); }
-  CFX_XMLNode* GetFirstChild() const { return first_child_.get(); }
-  CFX_XMLNode* GetNextSibling() const { return next_sibling_.get(); }
+  CFX_XMLNode* GetParent() const { return parent_; }
+  CFX_XMLNode* GetFirstChild() const { return first_child_; }
+  CFX_XMLNode* GetNextSibling() const { return next_sibling_; }
 
-  void AppendChild(std::unique_ptr<CFX_XMLNode> pNode);
-  void InsertChildNode(std::unique_ptr<CFX_XMLNode> pNode, int32_t index);
+  void AppendChild(CFX_XMLNode* pNode);
+  void InsertChildNode(CFX_XMLNode* pNode, int32_t index);
   void RemoveChildNode(CFX_XMLNode* pNode);
   void DeleteChildren();
 
-  CFX_XMLNode* GetLastChildForTesting() const { return last_child_.Get(); }
-  CFX_XMLNode* GetPrevSiblingForTesting() const { return prev_sibling_.Get(); }
+  CFX_XMLNode* GetLastChildForTesting() const { return last_child_; }
+  CFX_XMLNode* GetPrevSiblingForTesting() const { return prev_sibling_; }
 
  protected:
   WideString EncodeEntities(const WideString& value);
 
  private:
-  // A node owns its first child and it owns its next sibling. The rest
-  // are unowned pointers.
-  UnownedPtr<CFX_XMLNode> parent_;
-  UnownedPtr<CFX_XMLNode> last_child_;
-  UnownedPtr<CFX_XMLNode> prev_sibling_;
-  std::unique_ptr<CFX_XMLNode> first_child_;
-  std::unique_ptr<CFX_XMLNode> next_sibling_;
+  // The nodes are owned by the XML document. We do not know what order the
+  // nodes will be destroyed in so they can not be UnownedPtrs.
+  CFX_XMLNode* parent_ = nullptr;
+  CFX_XMLNode* first_child_ = nullptr;
+  CFX_XMLNode* last_child_ = nullptr;
+  CFX_XMLNode* next_sibling_ = nullptr;
+  CFX_XMLNode* prev_sibling_ = nullptr;
 };
 
 #endif  // CORE_FXCRT_XML_CFX_XMLNODE_H_
diff --git a/core/fxcrt/xml/cfx_xmlnode_unittest.cpp b/core/fxcrt/xml/cfx_xmlnode_unittest.cpp
index 1c69069942..ec56603a58 100644
--- a/core/fxcrt/xml/cfx_xmlnode_unittest.cpp
+++ b/core/fxcrt/xml/cfx_xmlnode_unittest.cpp
@@ -2,274 +2,227 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#include <utility>
-
 #include "core/fxcrt/xml/cfx_xmlelement.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "testing/test_support.h"
-#include "third_party/base/ptr_util.h"
 
 TEST(CFX_XMLNodeTest, GetParent) {
-  auto node1 = pdfium::MakeUnique<CFX_XMLElement>(L"node");
-  auto child2 = pdfium::MakeUnique<CFX_XMLElement>(L"node2");
-  auto child3 = pdfium::MakeUnique<CFX_XMLElement>(L"node3");
-
-  CFX_XMLElement* node2 = child2.get();
-  CFX_XMLElement* node3 = child3.get();
+  CFX_XMLElement node1(L"node");
+  CFX_XMLElement node2(L"node2");
+  CFX_XMLElement node3(L"node3");
 
-  node1->AppendChild(std::move(child2));
-  node2->AppendChild(std::move(child3));
+  node1.AppendChild(&node2);
+  node2.AppendChild(&node3);
 
-  EXPECT_EQ(nullptr, node1->GetParent());
-  EXPECT_EQ(node1.get(), node2->GetParent());
-  EXPECT_EQ(node2, node3->GetParent());
+  EXPECT_EQ(nullptr, node1.GetParent());
+  EXPECT_EQ(&node1, node2.GetParent());
+  EXPECT_EQ(&node2, node3.GetParent());
 }
 
 TEST(CFX_XMLNodeTest, GetRoot) {
-  auto node1 = pdfium::MakeUnique<CFX_XMLElement>(L"node");
-  auto child2 = pdfium::MakeUnique<CFX_XMLElement>(L"node2");
-  auto child3 = pdfium::MakeUnique<CFX_XMLElement>(L"node3");
+  CFX_XMLElement node1(L"node");
+  CFX_XMLElement node2(L"node2");
+  CFX_XMLElement node3(L"node3");
 
-  CFX_XMLElement* node2 = child2.get();
-  CFX_XMLElement* node3 = child3.get();
+  node1.AppendChild(&node2);
+  node2.AppendChild(&node3);
 
-  node1->AppendChild(std::move(child2));
-  node2->AppendChild(std::move(child3));
-
-  EXPECT_EQ(node1.get(), node1->GetRoot());
-  EXPECT_EQ(node1.get(), node2->GetRoot());
-  EXPECT_EQ(node1.get(), node3->GetRoot());
+  EXPECT_EQ(&node1, node1.GetRoot());
+  EXPECT_EQ(&node1, node2.GetRoot());
+  EXPECT_EQ(&node1, node3.GetRoot());
 }
 
 TEST(CFX_XMLNodeTest, GetChildren) {
-  auto node1 = pdfium::MakeUnique<CFX_XMLElement>(L"node");
-  auto child2 = pdfium::MakeUnique<CFX_XMLElement>(L"node2");
-  auto child3 = pdfium::MakeUnique<CFX_XMLElement>(L"node3");
-  auto child4 = pdfium::MakeUnique<CFX_XMLElement>(L"node4");
-
-  CFX_XMLElement* node2 = child2.get();
-  CFX_XMLElement* node3 = child3.get();
-  CFX_XMLElement* node4 = child4.get();
+  CFX_XMLElement node1(L"node");
+  CFX_XMLElement node2(L"node2");
+  CFX_XMLElement node3(L"node3");
+  CFX_XMLElement node4(L"node4");
 
-  node1->AppendChild(std::move(child2));
-  node1->AppendChild(std::move(child4));
-  node2->AppendChild(std::move(child3));
+  node1.AppendChild(&node2);
+  node1.AppendChild(&node4);
+  node2.AppendChild(&node3);
 
-  EXPECT_EQ(node2, node1->GetFirstChild());
+  EXPECT_EQ(&node2, node1.GetFirstChild());
 
-  EXPECT_EQ(node4, node2->GetNextSibling());
-  EXPECT_EQ(node3, node2->GetFirstChild());
+  EXPECT_EQ(&node4, node2.GetNextSibling());
+  EXPECT_EQ(&node3, node2.GetFirstChild());
 
-  EXPECT_TRUE(node3->GetNextSibling() == nullptr);
-  EXPECT_TRUE(node3->GetFirstChild() == nullptr);
+  EXPECT_TRUE(node3.GetNextSibling() == nullptr);
+  EXPECT_TRUE(node3.GetFirstChild() == nullptr);
 
-  EXPECT_TRUE(node4->GetNextSibling() == nullptr);
-  EXPECT_TRUE(node4->GetFirstChild() == nullptr);
+  EXPECT_TRUE(node4.GetNextSibling() == nullptr);
+  EXPECT_TRUE(node4.GetFirstChild() == nullptr);
 }
 
 TEST(CFX_XMLNodeTest, DeleteChildren) {
-  auto node1 = pdfium::MakeUnique<CFX_XMLElement>(L"node");
-  auto child2 = pdfium::MakeUnique<CFX_XMLElement>(L"node2");
-  auto child3 = pdfium::MakeUnique<CFX_XMLElement>(L"node3");
-  auto child4 = pdfium::MakeUnique<CFX_XMLElement>(L"node4");
-
-  CFX_XMLElement* node2 = child2.get();
-  // CFX_XMLElement* node3 = child3.get();
-  // CFX_XMLElement* node4 = child4.get();
-
-  node1->AppendChild(std::move(child2));
-  node1->AppendChild(std::move(child4));
-  node2->AppendChild(std::move(child3));
-
-  node1->DeleteChildren();
-  EXPECT_TRUE(node1->GetFirstChild() == nullptr);
-  EXPECT_TRUE(node1->GetLastChildForTesting() == nullptr);
+  CFX_XMLElement node1(L"node");
+  CFX_XMLElement node2(L"node2");
+  CFX_XMLElement node3(L"node3");
+  CFX_XMLElement node4(L"node4");
 
-  // TODO(dsinclair): This isn't true currently but will be true when
-  // we own the nodes in an XML document. (Currently nodes are unique_ptrs
-  // so the objects have been deleted by this point.)
+  node1.AppendChild(&node2);
+  node1.AppendChild(&node4);
+  node2.AppendChild(&node3);
 
-  // EXPECT_TRUE(node2->GetParent() == nullptr);
-  // EXPECT_TRUE(node4->GetParent() == nullptr);
+  node1.DeleteChildren();
+  EXPECT_TRUE(node1.GetFirstChild() == nullptr);
+  EXPECT_TRUE(node2.GetParent() == nullptr);
+  EXPECT_TRUE(node4.GetParent() == nullptr);
 
-  // // node2 and node4 should no longer be siblings.
-  // EXPECT_TRUE(node2->GetNextSibling() == nullptr);
-  // EXPECT_TRUE(node4->GetPrevSiblingForTesting() == nullptr);
+  // node2 and node4 should no longer be siblings.
+  EXPECT_TRUE(node2.GetNextSibling() == nullptr);
+  EXPECT_TRUE(node4.GetPrevSiblingForTesting() == nullptr);
 
   // Deleting children doesn't change deleted substructure
-  // EXPECT_EQ(node3, node2->GetFirstChild());
-  // EXPECT_TRUE(node3->GetParent() == node2);
+  EXPECT_EQ(&node3, node2.GetFirstChild());
+  EXPECT_TRUE(node3.GetParent() == &node2);
 }
 
 TEST(CFX_XMLNodeTest, AddingChildren) {
-  auto node1 = pdfium::MakeUnique<CFX_XMLElement>(L"node");
-  auto child2 = pdfium::MakeUnique<CFX_XMLElement>(L"node2");
-  auto child3 = pdfium::MakeUnique<CFX_XMLElement>(L"node3");
-  auto child4 = pdfium::MakeUnique<CFX_XMLElement>(L"node4");
-  auto child5 = pdfium::MakeUnique<CFX_XMLElement>(L"node5");
+  CFX_XMLElement node1(L"node");
+  CFX_XMLElement node2(L"node2");
+  CFX_XMLElement node3(L"node3");
 
-  CFX_XMLElement* node2 = child2.get();
-  CFX_XMLElement* node3 = child3.get();
-  CFX_XMLElement* node4 = child4.get();
-  CFX_XMLElement* node5 = child5.get();
+  node1.AppendChild(&node2);
+  node1.AppendChild(&node3);
 
-  node1->AppendChild(std::move(child2));
-  node1->AppendChild(std::move(child3));
+  EXPECT_EQ(&node1, node2.GetParent());
+  EXPECT_EQ(&node1, node3.GetParent());
 
-  EXPECT_EQ(node1.get(), node2->GetParent());
-  EXPECT_EQ(node1.get(), node3->GetParent());
-
-  EXPECT_EQ(node2, node1->GetFirstChild());
-  EXPECT_EQ(node3, node2->GetNextSibling());
-  EXPECT_TRUE(node3->GetNextSibling() == nullptr);
+  EXPECT_EQ(&node2, node1.GetFirstChild());
+  EXPECT_EQ(&node3, node2.GetNextSibling());
+  EXPECT_TRUE(node3.GetNextSibling() == nullptr);
 
   // Insert to negative appends.
-  node1->InsertChildNode(std::move(child4), -1);
-  EXPECT_EQ(node1.get(), node4->GetParent());
-  EXPECT_EQ(node4, node3->GetNextSibling());
-  EXPECT_TRUE(node4->GetNextSibling() == nullptr);
-
-  node1->InsertChildNode(std::move(child5), 1);
-  EXPECT_EQ(node1.get(), node5->GetParent());
-  EXPECT_EQ(node2, node1->GetFirstChild());
-  EXPECT_EQ(node5, node2->GetNextSibling());
-  EXPECT_EQ(node3, node5->GetNextSibling());
-  EXPECT_EQ(node4, node3->GetNextSibling());
-  EXPECT_TRUE(node4->GetNextSibling() == nullptr);
+  CFX_XMLElement node4(L"node4");
+  node1.InsertChildNode(&node4, -1);
+  EXPECT_EQ(&node1, node4.GetParent());
+  EXPECT_EQ(&node4, node3.GetNextSibling());
+  EXPECT_TRUE(node4.GetNextSibling() == nullptr);
+
+  CFX_XMLElement node5(L"node5");
+  node1.InsertChildNode(&node5, 1);
+  EXPECT_EQ(&node1, node5.GetParent());
+  EXPECT_EQ(&node2, node1.GetFirstChild());
+  EXPECT_EQ(&node5, node2.GetNextSibling());
+  EXPECT_EQ(&node3, node5.GetNextSibling());
+  EXPECT_EQ(&node4, node3.GetNextSibling());
+  EXPECT_TRUE(node4.GetNextSibling() == nullptr);
+}
+
+#ifndef NDEBUG
+TEST(CFX_XMLNodeTest, DuplicateInsertOfNode) {
+  CFX_XMLElement node1(L"node");
+  CFX_XMLElement node2(L"node2");
+
+  node1.AppendChild(&node2);
+  EXPECT_DEATH(node1.AppendChild(&node2), "");
 }
+#endif  // NDEBUG
 
 TEST(CFX_XMLNodeTest, RemovingMiddleChild) {
-  auto node1 = pdfium::MakeUnique<CFX_XMLElement>(L"node");
-  auto child2 = pdfium::MakeUnique<CFX_XMLElement>(L"node2");
-  auto child3 = pdfium::MakeUnique<CFX_XMLElement>(L"node3");
-  auto child4 = pdfium::MakeUnique<CFX_XMLElement>(L"node4");
-
-  CFX_XMLElement* node2 = child2.get();
-  CFX_XMLElement* node3 = child3.get();
-  CFX_XMLElement* node4 = child4.get();
-
-  node1->AppendChild(std::move(child2));
-  node1->AppendChild(std::move(child3));
-  node1->AppendChild(std::move(child4));
-
-  EXPECT_EQ(node2, node1->GetFirstChild());
-  EXPECT_EQ(node3, node2->GetNextSibling());
-  EXPECT_EQ(node4, node3->GetNextSibling());
-  EXPECT_TRUE(node4->GetNextSibling() == nullptr);
-
-  node1->RemoveChildNode(node3);
-  // Node is released by parent, so need to take ownership
-  child3 = pdfium::WrapUnique(node3);
-
-  EXPECT_TRUE(node3->GetParent() == nullptr);
-  EXPECT_TRUE(node3->GetNextSibling() == nullptr);
-  EXPECT_TRUE(node3->GetPrevSiblingForTesting() == nullptr);
-
-  EXPECT_EQ(node2, node1->GetFirstChild());
-  EXPECT_EQ(node4, node2->GetNextSibling());
-  EXPECT_EQ(node2, node4->GetPrevSiblingForTesting());
-  EXPECT_TRUE(node4->GetNextSibling() == nullptr);
+  CFX_XMLElement node1(L"node1");
+  CFX_XMLElement node2(L"node2");
+  CFX_XMLElement node3(L"node3");
+  CFX_XMLElement node4(L"node4");
+
+  node1.AppendChild(&node2);
+  node1.AppendChild(&node3);
+  node1.AppendChild(&node4);
+
+  EXPECT_EQ(&node2, node1.GetFirstChild());
+  EXPECT_EQ(&node3, node2.GetNextSibling());
+  EXPECT_EQ(&node4, node3.GetNextSibling());
+  EXPECT_TRUE(node4.GetNextSibling() == nullptr);
+
+  node1.RemoveChildNode(&node3);
+  EXPECT_TRUE(node3.GetParent() == nullptr);
+  EXPECT_TRUE(node3.GetNextSibling() == nullptr);
+  EXPECT_TRUE(node3.GetPrevSiblingForTesting() == nullptr);
+
+  EXPECT_EQ(&node2, node1.GetFirstChild());
+  EXPECT_EQ(&node4, node2.GetNextSibling());
+  EXPECT_EQ(&node2, node4.GetPrevSiblingForTesting());
+  EXPECT_TRUE(node4.GetNextSibling() == nullptr);
 }
 
 TEST(CFX_XMLNodeTest, RemovingFirstChild) {
-  auto node1 = pdfium::MakeUnique<CFX_XMLElement>(L"node");
-  auto child2 = pdfium::MakeUnique<CFX_XMLElement>(L"node2");
-  auto child3 = pdfium::MakeUnique<CFX_XMLElement>(L"node3");
-  auto child4 = pdfium::MakeUnique<CFX_XMLElement>(L"node4");
-
-  CFX_XMLElement* node2 = child2.get();
-  CFX_XMLElement* node3 = child3.get();
-  CFX_XMLElement* node4 = child4.get();
-
-  node1->AppendChild(std::move(child2));
-  node1->AppendChild(std::move(child3));
-  node1->AppendChild(std::move(child4));
-
-  EXPECT_EQ(node2, node1->GetFirstChild());
-  EXPECT_EQ(node3, node2->GetNextSibling());
-  EXPECT_EQ(node4, node3->GetNextSibling());
-  EXPECT_TRUE(node4->GetNextSibling() == nullptr);
-
-  node1->RemoveChildNode(node2);
-  // Node is released by parent, so need to take ownership
-  child2 = pdfium::WrapUnique(node2);
-
-  EXPECT_TRUE(node2->GetParent() == nullptr);
-  EXPECT_TRUE(node2->GetNextSibling() == nullptr);
-  EXPECT_TRUE(node2->GetPrevSiblingForTesting() == nullptr);
-
-  EXPECT_EQ(node3, node1->GetFirstChild());
-  EXPECT_TRUE(node3->GetPrevSiblingForTesting() == nullptr);
-  EXPECT_EQ(node4, node3->GetNextSibling());
-  EXPECT_TRUE(node4->GetNextSibling() == nullptr);
+  CFX_XMLElement node1(L"node1");
+  CFX_XMLElement node2(L"node2");
+  CFX_XMLElement node3(L"node3");
+  CFX_XMLElement node4(L"node4");
+
+  node1.AppendChild(&node2);
+  node1.AppendChild(&node3);
+  node1.AppendChild(&node4);
+
+  EXPECT_EQ(&node2, node1.GetFirstChild());
+  EXPECT_EQ(&node3, node2.GetNextSibling());
+  EXPECT_EQ(&node4, node3.GetNextSibling());
+  EXPECT_TRUE(node4.GetNextSibling() == nullptr);
+
+  node1.RemoveChildNode(&node2);
+  EXPECT_TRUE(node2.GetParent() == nullptr);
+  EXPECT_TRUE(node2.GetNextSibling() == nullptr);
+  EXPECT_TRUE(node2.GetPrevSiblingForTesting() == nullptr);
+
+  EXPECT_EQ(&node3, node1.GetFirstChild());
+  EXPECT_TRUE(node3.GetPrevSiblingForTesting() == nullptr);
+  EXPECT_EQ(&node4, node3.GetNextSibling());
+  EXPECT_TRUE(node4.GetNextSibling() == nullptr);
 }
 
 TEST(CFX_XMLNodeTest, RemovingLastChild) {
-  auto node1 = pdfium::MakeUnique<CFX_XMLElement>(L"node");
-  auto child2 = pdfium::MakeUnique<CFX_XMLElement>(L"node2");
-  auto child3 = pdfium::MakeUnique<CFX_XMLElement>(L"node3");
-  auto child4 = pdfium::MakeUnique<CFX_XMLElement>(L"node4");
-
-  CFX_XMLElement* node2 = child2.get();
-  CFX_XMLElement* node3 = child3.get();
-  CFX_XMLElement* node4 = child4.get();
-
-  node1->AppendChild(std::move(child2));
-  node1->AppendChild(std::move(child3));
-  node1->AppendChild(std::move(child4));
-
-  EXPECT_EQ(node2, node1->GetFirstChild());
-  EXPECT_EQ(node3, node2->GetNextSibling());
-  EXPECT_EQ(node4, node3->GetNextSibling());
-  EXPECT_TRUE(node4->GetNextSibling() == nullptr);
-
-  node1->RemoveChildNode(node4);
-  // Node is released by parent, so need to take ownership
-  child4 = pdfium::WrapUnique(node4);
-
-  EXPECT_TRUE(node4->GetParent() == nullptr);
-  EXPECT_TRUE(node4->GetNextSibling() == nullptr);
-  EXPECT_TRUE(node4->GetPrevSiblingForTesting() == nullptr);
-
-  EXPECT_EQ(node2, node1->GetFirstChild());
-  EXPECT_EQ(node3, node2->GetNextSibling());
-  EXPECT_TRUE(node3->GetNextSibling() == nullptr);
+  CFX_XMLElement node1(L"node1");
+  CFX_XMLElement node2(L"node2");
+  CFX_XMLElement node3(L"node3");
+  CFX_XMLElement node4(L"node4");
+
+  node1.AppendChild(&node2);
+  node1.AppendChild(&node3);
+  node1.AppendChild(&node4);
+
+  EXPECT_EQ(&node2, node1.GetFirstChild());
+  EXPECT_EQ(&node3, node2.GetNextSibling());
+  EXPECT_EQ(&node4, node3.GetNextSibling());
+  EXPECT_TRUE(node4.GetNextSibling() == nullptr);
+
+  node1.RemoveChildNode(&node4);
+  EXPECT_TRUE(node4.GetParent() == nullptr);
+  EXPECT_TRUE(node4.GetNextSibling() == nullptr);
+  EXPECT_TRUE(node4.GetPrevSiblingForTesting() == nullptr);
+
+  EXPECT_EQ(&node2, node1.GetFirstChild());
+  EXPECT_EQ(&node3, node2.GetNextSibling());
+  EXPECT_TRUE(node3.GetNextSibling() == nullptr);
 }
 
 TEST(CFX_XMLNodeTest, RemovingOnlyChild) {
-  auto node1 = pdfium::MakeUnique<CFX_XMLElement>(L"node");
-  auto child2 = pdfium::MakeUnique<CFX_XMLElement>(L"node2");
+  CFX_XMLElement node1(L"node1");
+  CFX_XMLElement node2(L"node2");
 
-  CFX_XMLElement* node2 = child2.get();
+  node1.AppendChild(&node2);
 
-  node1->AppendChild(std::move(child2));
+  EXPECT_EQ(&node2, node1.GetFirstChild());
+  EXPECT_TRUE(node2.GetNextSibling() == nullptr);
 
-  EXPECT_EQ(node2, node1->GetFirstChild());
-  EXPECT_TRUE(node2->GetNextSibling() == nullptr);
+  node1.RemoveChildNode(&node2);
+  EXPECT_TRUE(node2.GetParent() == nullptr);
 
-  node1->RemoveChildNode(node2);
-  // Node is released by parent, so need to take ownership
-  child2 = pdfium::WrapUnique(node2);
-
-  EXPECT_TRUE(node2->GetParent() == nullptr);
-
-  EXPECT_TRUE(node1->GetFirstChild() == nullptr);
-  EXPECT_TRUE(node2->GetNextSibling() == nullptr);
-  EXPECT_TRUE(node2->GetPrevSiblingForTesting() == nullptr);
+  EXPECT_TRUE(node1.GetFirstChild() == nullptr);
+  EXPECT_TRUE(node2.GetNextSibling() == nullptr);
+  EXPECT_TRUE(node2.GetPrevSiblingForTesting() == nullptr);
 }
 
 TEST(CFX_XMLNodeTest, RemoveMissingChild) {
-  auto node1 = pdfium::MakeUnique<CFX_XMLElement>(L"node");
-  auto child2 = pdfium::MakeUnique<CFX_XMLElement>(L"node2");
-  auto child3 = pdfium::MakeUnique<CFX_XMLElement>(L"node3");
-
-  CFX_XMLElement* node2 = child2.get();
-  CFX_XMLElement* node3 = child3.get();
+  CFX_XMLElement node1(L"node1");
+  CFX_XMLElement node2(L"node2");
+  CFX_XMLElement node3(L"node3");
 
-  node1->AppendChild(std::move(child2));
-  node1->RemoveChildNode(node3);
+  node1.AppendChild(&node2);
+  node1.RemoveChildNode(&node3);
 
-  EXPECT_TRUE(node3->GetParent() == nullptr);
-  EXPECT_EQ(node2, node1->GetFirstChild());
-  EXPECT_TRUE(node2->GetNextSibling() == nullptr);
+  EXPECT_TRUE(node3.GetParent() == nullptr);
+  EXPECT_EQ(&node2, node1.GetFirstChild());
+  EXPECT_TRUE(node2.GetNextSibling() == nullptr);
 }
diff --git a/core/fxcrt/xml/cfx_xmlparser.cpp b/core/fxcrt/xml/cfx_xmlparser.cpp
index c7a81afc16..b7dbd19eab 100644
--- a/core/fxcrt/xml/cfx_xmlparser.cpp
+++ b/core/fxcrt/xml/cfx_xmlparser.cpp
@@ -16,6 +16,7 @@
 #include "core/fxcrt/fx_extension.h"
 #include "core/fxcrt/fx_safe_types.h"
 #include "core/fxcrt/xml/cfx_xmlchardata.h"
+#include "core/fxcrt/xml/cfx_xmldocument.h"
 #include "core/fxcrt/xml/cfx_xmlelement.h"
 #include "core/fxcrt/xml/cfx_xmlinstruction.h"
 #include "core/fxcrt/xml/cfx_xmlnode.h"
@@ -58,10 +59,7 @@ bool CFX_XMLParser::IsXMLNameChar(wchar_t ch, bool bFirstChar) {
          (!bFirstChar || it->bStartChar);
 }
 
-CFX_XMLParser::CFX_XMLParser(CFX_XMLNode* pParent,
-                             const RetainPtr<IFX_SeekableReadStream>& pStream)
-    : m_pParent(pParent) {
-  ASSERT(m_pParent);
+CFX_XMLParser::CFX_XMLParser(const RetainPtr<IFX_SeekableReadStream>& pStream) {
   ASSERT(pStream);
 
   auto proxy = pdfium::MakeRetain<CFX_SeekableStreamProxy>(pStream);
@@ -89,56 +87,51 @@ CFX_XMLParser::CFX_XMLParser(CFX_XMLNode* pParent,
 
 CFX_XMLParser::~CFX_XMLParser() = default;
 
-bool CFX_XMLParser::Parse() {
+std::unique_ptr<CFX_XMLDocument> CFX_XMLParser::Parse() {
+  auto doc = pdfium::MakeUnique<CFX_XMLDocument>();
+  current_node_ = doc->GetRoot();
+
   int32_t iCount = 0;
   while (true) {
     FX_XmlSyntaxResult result = DoSyntaxParse();
     if (result == FX_XmlSyntaxResult::Error)
-      return false;
+      return nullptr;
     if (result == FX_XmlSyntaxResult::EndOfString)
       break;
 
     switch (result) {
       case FX_XmlSyntaxResult::InstructionClose:
-        if (m_pChild && m_pChild->GetType() != FX_XMLNODE_Instruction)
-          return false;
-
-        m_pChild = m_pParent;
+        if (current_node_ && current_node_->GetType() == FX_XMLNODE_Instruction)
+          current_node_ = current_node_->GetParent();
         break;
       case FX_XmlSyntaxResult::ElementClose: {
-        if (m_pChild->GetType() != FX_XMLNODE_Element)
-          return false;
+        if (current_node_->GetType() != FX_XMLNODE_Element)
+          return nullptr;
 
         WideString element_name = GetTextData();
         if (element_name.GetLength() > 0 &&
-            element_name != static_cast<CFX_XMLElement*>(m_pChild)->GetName()) {
-          return false;
+            element_name !=
+                static_cast<CFX_XMLElement*>(current_node_)->GetName()) {
+          return nullptr;
         }
 
-        if (!m_pChild || !m_pChild->GetParent())
-          return false;
-
-        m_pParent = m_pChild->GetParent();
-        m_pChild = m_pParent;
+        current_node_ = current_node_->GetParent();
         iCount++;
         break;
       }
       case FX_XmlSyntaxResult::TargetName: {
         WideString target_name = GetTextData();
         if (target_name == L"originalXFAVersion" || target_name == L"acrobat") {
-          auto child = pdfium::MakeUnique<CFX_XMLInstruction>(target_name);
-          m_pChild = child.get();
-          m_pParent->AppendChild(std::move(child));
-        } else {
-          m_pChild = nullptr;
+          auto* node = doc->CreateNode<CFX_XMLInstruction>(target_name);
+          current_node_->AppendChild(node);
+          current_node_ = node;
         }
         break;
       }
       case FX_XmlSyntaxResult::TagName: {
-        auto child = pdfium::MakeUnique<CFX_XMLElement>(GetTextData());
-        m_pChild = child.get();
-        m_pParent->AppendChild(std::move(child));
-        m_pParent = m_pChild;
+        auto* child = doc->CreateNode<CFX_XMLElement>(GetTextData());
+        current_node_->AppendChild(child);
+        current_node_ = child;
         break;
       }
       case FX_XmlSyntaxResult::AttriName: {
@@ -146,35 +139,29 @@ bool CFX_XMLParser::Parse() {
         break;
       }
       case FX_XmlSyntaxResult::AttriValue:
-        if (m_pChild && m_pChild->GetType() == FX_XMLNODE_Element) {
-          static_cast<CFX_XMLElement*>(m_pChild)->SetAttribute(
-              current_attribute_name_, GetTextData());
+        if (current_node_ && current_node_->GetType() == FX_XMLNODE_Element) {
+          static_cast<CFX_XMLElement*>(current_node_)
+              ->SetAttribute(current_attribute_name_, GetTextData());
         }
         current_attribute_name_.clear();
         break;
       case FX_XmlSyntaxResult::Text: {
-        auto child = pdfium::MakeUnique<CFX_XMLText>(GetTextData());
-        m_pChild = child.get();
-        m_pParent->AppendChild(std::move(child));
-        m_pChild = m_pParent;
+        current_node_->AppendChild(doc->CreateNode<CFX_XMLText>(GetTextData()));
         break;
       }
       case FX_XmlSyntaxResult::CData: {
-        auto child = pdfium::MakeUnique<CFX_XMLCharData>(GetTextData());
-        m_pChild = child.get();
-        m_pParent->AppendChild(std::move(child));
-        m_pChild = m_pParent;
+        current_node_->AppendChild(
+            doc->CreateNode<CFX_XMLCharData>(GetTextData()));
         break;
       }
       case FX_XmlSyntaxResult::TargetData: {
         WideString target_data = GetTextData();
-        if (m_pChild) {
-          if (m_pChild->GetType() != FX_XMLNODE_Instruction)
-            return false;
-
-          auto* instruction = static_cast<CFX_XMLInstruction*>(m_pChild);
-          if (!target_data.IsEmpty())
-            instruction->AppendData(target_data);
+        if (current_node_ &&
+            current_node_->GetType() == FX_XMLNODE_Instruction) {
+          if (target_data.IsEmpty())
+            break;
+          static_cast<CFX_XMLInstruction*>(current_node_)
+              ->AppendData(target_data);
         }
         break;
       }
@@ -185,7 +172,7 @@ bool CFX_XMLParser::Parse() {
         break;
     }
   }
-  return !m_pParent || m_pParent->GetParent() ? false : GetStatus();
+  return doc;
 }
 
 FX_XmlSyntaxResult CFX_XMLParser::DoSyntaxParse() {
diff --git a/core/fxcrt/xml/cfx_xmlparser.h b/core/fxcrt/xml/cfx_xmlparser.h
index e2a2d5b30f..6bf1946402 100644
--- a/core/fxcrt/xml/cfx_xmlparser.h
+++ b/core/fxcrt/xml/cfx_xmlparser.h
@@ -15,6 +15,7 @@
 #include "core/fxcrt/retain_ptr.h"
 #include "core/fxcrt/xml/cfx_xmlnode.h"
 
+class CFX_XMLDocument;
 class CFX_XMLElement;
 class CFX_XMLNode;
 class IFX_SeekableReadStream;
@@ -41,11 +42,10 @@ class CFX_XMLParser {
  public:
   static bool IsXMLNameChar(wchar_t ch, bool bFirstChar);
 
-  CFX_XMLParser(CFX_XMLNode* pParent,
-                const RetainPtr<IFX_SeekableReadStream>& pStream);
+  explicit CFX_XMLParser(const RetainPtr<IFX_SeekableReadStream>& pStream);
   virtual ~CFX_XMLParser();
 
-  bool Parse();
+  std::unique_ptr<CFX_XMLDocument> Parse();
 
  protected:
   FX_XmlSyntaxResult DoSyntaxParse();
@@ -74,8 +74,7 @@ class CFX_XMLParser {
   void ParseTextChar(wchar_t ch);
   bool GetStatus() const;
 
-  CFX_XMLNode* m_pParent;
-  CFX_XMLNode* m_pChild = nullptr;
+  CFX_XMLNode* current_node_ = nullptr;
   WideString current_attribute_name_;
   RetainPtr<IFX_SeekableReadStream> m_pStream;
   FX_FILESIZE m_Start = 0;  // Start position in m_Buffer
diff --git a/core/fxcrt/xml/cfx_xmlparser_unittest.cpp b/core/fxcrt/xml/cfx_xmlparser_unittest.cpp
index 73d6685dad..7ca242211d 100644
--- a/core/fxcrt/xml/cfx_xmlparser_unittest.cpp
+++ b/core/fxcrt/xml/cfx_xmlparser_unittest.cpp
@@ -8,7 +8,9 @@
 
 #include "core/fxcrt/cfx_memorystream.h"
 #include "core/fxcrt/fx_codepage.h"
+#include "core/fxcrt/xml/cfx_xmldocument.h"
 #include "core/fxcrt/xml/cfx_xmlelement.h"
+#include "core/fxcrt/xml/cfx_xmlinstruction.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "testing/test_support.h"
 #include "third_party/base/ptr_util.h"
@@ -17,9 +19,8 @@ namespace {
 
 class CFX_XMLTestParser : public CFX_XMLParser {
  public:
-  CFX_XMLTestParser(CFX_XMLNode* pParent,
-                    const RetainPtr<IFX_SeekableStream>& pStream)
-      : CFX_XMLParser(pParent, pStream) {}
+  explicit CFX_XMLTestParser(const RetainPtr<IFX_SeekableStream>& pStream)
+      : CFX_XMLParser(pStream) {}
 
   ~CFX_XMLTestParser() override = default;
 
@@ -52,9 +53,7 @@ TEST(CFX_XMLParserTest, CData) {
       L"  ";
 
   auto stream = MakeProxy(input);
-  auto root = pdfium::MakeUnique<CFX_XMLElement>(L"ROOT");
-
-  CFX_XMLTestParser parser(root.get(), stream);
+  CFX_XMLTestParser parser(stream);
   ASSERT_EQ(FX_XmlSyntaxResult::ElementOpen, parser.DoSyntaxParse());
   ASSERT_EQ(FX_XmlSyntaxResult::TagName, parser.DoSyntaxParse());
   ASSERT_EQ(L"script", parser.GetTextData());
@@ -98,9 +97,7 @@ TEST(CFX_XMLParserTest, CDataWithInnerScript) {
       L"  ";
 
   auto stream = MakeProxy(input);
-  auto root = pdfium::MakeUnique<CFX_XMLElement>(L"ROOT");
-
-  CFX_XMLTestParser parser(root.get(), stream);
+  CFX_XMLTestParser parser(stream);
   ASSERT_EQ(FX_XmlSyntaxResult::ElementOpen, parser.DoSyntaxParse());
   ASSERT_EQ(FX_XmlSyntaxResult::TagName, parser.DoSyntaxParse());
   ASSERT_EQ(L"script", parser.GetTextData());
@@ -133,9 +130,7 @@ TEST(CFX_XMLParserTest, ArrowBangArrow) {
       "</script>";
 
   auto stream = MakeProxy(input);
-  auto root = pdfium::MakeUnique<CFX_XMLElement>(L"ROOT");
-
-  CFX_XMLTestParser parser(root.get(), stream);
+  CFX_XMLTestParser parser(stream);
   ASSERT_EQ(FX_XmlSyntaxResult::ElementOpen, parser.DoSyntaxParse());
   ASSERT_EQ(FX_XmlSyntaxResult::TagName, parser.DoSyntaxParse());
 
@@ -166,9 +161,7 @@ TEST(CFX_XMLParserTest, ArrowBangBracketArrow) {
       "</script>";
 
   auto stream = MakeProxy(input);
-  auto root = pdfium::MakeUnique<CFX_XMLElement>(L"ROOT");
-
-  CFX_XMLTestParser parser(root.get(), stream);
+  CFX_XMLTestParser parser(stream);
   ASSERT_EQ(FX_XmlSyntaxResult::ElementOpen, parser.DoSyntaxParse());
   ASSERT_EQ(FX_XmlSyntaxResult::TagName, parser.DoSyntaxParse());
   ASSERT_EQ(L"script", parser.GetTextData());
@@ -194,9 +187,7 @@ TEST(CFX_XMLParserTest, IncompleteCData) {
       "</script>";
 
   auto stream = MakeProxy(input);
-  auto root = pdfium::MakeUnique<CFX_XMLElement>(L"ROOT");
-
-  CFX_XMLTestParser parser(root.get(), stream);
+  CFX_XMLTestParser parser(stream);
   ASSERT_EQ(FX_XmlSyntaxResult::ElementOpen, parser.DoSyntaxParse());
   ASSERT_EQ(FX_XmlSyntaxResult::TagName, parser.DoSyntaxParse());
   ASSERT_EQ(L"script", parser.GetTextData());
@@ -222,9 +213,7 @@ TEST(CFX_XMLParserTest, UnClosedCData) {
       "</script>";
 
   auto stream = MakeProxy(input);
-  auto root = pdfium::MakeUnique<CFX_XMLElement>(L"ROOT");
-
-  CFX_XMLTestParser parser(root.get(), stream);
+  CFX_XMLTestParser parser(stream);
   ASSERT_EQ(FX_XmlSyntaxResult::ElementOpen, parser.DoSyntaxParse());
   ASSERT_EQ(FX_XmlSyntaxResult::TagName, parser.DoSyntaxParse());
   ASSERT_EQ(L"script", parser.GetTextData());
@@ -250,9 +239,7 @@ TEST(CFX_XMLParserTest, EmptyCData) {
       "</script>";
 
   auto stream = MakeProxy(input);
-  auto root = pdfium::MakeUnique<CFX_XMLElement>(L"ROOT");
-
-  CFX_XMLTestParser parser(root.get(), stream);
+  CFX_XMLTestParser parser(stream);
   ASSERT_EQ(FX_XmlSyntaxResult::ElementOpen, parser.DoSyntaxParse());
   ASSERT_EQ(FX_XmlSyntaxResult::TagName, parser.DoSyntaxParse());
   ASSERT_EQ(L"script", parser.GetTextData());
@@ -285,9 +272,7 @@ TEST(CFX_XMLParserTest, Comment) {
       "</script>";
 
   auto stream = MakeProxy(input);
-  auto root = pdfium::MakeUnique<CFX_XMLElement>(L"ROOT");
-
-  CFX_XMLTestParser parser(root.get(), stream);
+  CFX_XMLTestParser parser(stream);
   ASSERT_EQ(FX_XmlSyntaxResult::ElementOpen, parser.DoSyntaxParse());
   ASSERT_EQ(FX_XmlSyntaxResult::TagName, parser.DoSyntaxParse());
   ASSERT_EQ(L"script", parser.GetTextData());
@@ -317,9 +302,7 @@ TEST(CFX_XMLParserTest, IncorrectCommentStart) {
       "</script>";
 
   auto stream = MakeProxy(input);
-  auto root = pdfium::MakeUnique<CFX_XMLElement>(L"ROOT");
-
-  CFX_XMLTestParser parser(root.get(), stream);
+  CFX_XMLTestParser parser(stream);
   ASSERT_EQ(FX_XmlSyntaxResult::ElementOpen, parser.DoSyntaxParse());
   ASSERT_EQ(FX_XmlSyntaxResult::TagName, parser.DoSyntaxParse());
   ASSERT_EQ(L"script", parser.GetTextData());
@@ -349,9 +332,7 @@ TEST(CFX_XMLParserTest, CommentEmpty) {
       "</script>";
 
   auto stream = MakeProxy(input);
-  auto root = pdfium::MakeUnique<CFX_XMLElement>(L"ROOT");
-
-  CFX_XMLTestParser parser(root.get(), stream);
+  CFX_XMLTestParser parser(stream);
   ASSERT_EQ(FX_XmlSyntaxResult::ElementOpen, parser.DoSyntaxParse());
   ASSERT_EQ(FX_XmlSyntaxResult::TagName, parser.DoSyntaxParse());
   ASSERT_EQ(L"script", parser.GetTextData());
@@ -381,9 +362,7 @@ TEST(CFX_XMLParserTest, CommentThreeDash) {
       "</script>";
 
   auto stream = MakeProxy(input);
-  auto root = pdfium::MakeUnique<CFX_XMLElement>(L"ROOT");
-
-  CFX_XMLTestParser parser(root.get(), stream);
+  CFX_XMLTestParser parser(stream);
   ASSERT_EQ(FX_XmlSyntaxResult::ElementOpen, parser.DoSyntaxParse());
   ASSERT_EQ(FX_XmlSyntaxResult::TagName, parser.DoSyntaxParse());
   ASSERT_EQ(L"script", parser.GetTextData());
@@ -407,9 +386,7 @@ TEST(CFX_XMLParserTest, CommentTwoDash) {
       "</script>";
 
   auto stream = MakeProxy(input);
-  auto root = pdfium::MakeUnique<CFX_XMLElement>(L"ROOT");
-
-  CFX_XMLTestParser parser(root.get(), stream);
+  CFX_XMLTestParser parser(stream);
   ASSERT_EQ(FX_XmlSyntaxResult::ElementOpen, parser.DoSyntaxParse());
   ASSERT_EQ(FX_XmlSyntaxResult::TagName, parser.DoSyntaxParse());
   ASSERT_EQ(L"script", parser.GetTextData());
@@ -444,9 +421,7 @@ TEST(CFX_XMLParserTest, Entities) {
       "</script>";
 
   auto stream = MakeProxy(input);
-  auto root = pdfium::MakeUnique<CFX_XMLElement>(L"ROOT");
-
-  CFX_XMLTestParser parser(root.get(), stream);
+  CFX_XMLTestParser parser(stream);
   ASSERT_EQ(FX_XmlSyntaxResult::ElementOpen, parser.DoSyntaxParse());
   ASSERT_EQ(FX_XmlSyntaxResult::TagName, parser.DoSyntaxParse());
   ASSERT_EQ(L"script", parser.GetTextData());
@@ -474,9 +449,7 @@ TEST(CFX_XMLParserTest, EntityOverflowHex) {
       "</script>";
 
   auto stream = MakeProxy(input);
-  auto root = pdfium::MakeUnique<CFX_XMLElement>(L"ROOT");
-
-  CFX_XMLTestParser parser(root.get(), stream);
+  CFX_XMLTestParser parser(stream);
   ASSERT_EQ(FX_XmlSyntaxResult::ElementOpen, parser.DoSyntaxParse());
   ASSERT_EQ(FX_XmlSyntaxResult::TagName, parser.DoSyntaxParse());
   ASSERT_EQ(L"script", parser.GetTextData());
@@ -504,9 +477,7 @@ TEST(CFX_XMLParserTest, EntityOverflowDecimal) {
       "</script>";
 
   auto stream = MakeProxy(input);
-  auto root = pdfium::MakeUnique<CFX_XMLElement>(L"ROOT");
-
-  CFX_XMLTestParser parser(root.get(), stream);
+  CFX_XMLTestParser parser(stream);
   ASSERT_EQ(FX_XmlSyntaxResult::ElementOpen, parser.DoSyntaxParse());
   ASSERT_EQ(FX_XmlSyntaxResult::TagName, parser.DoSyntaxParse());
   ASSERT_EQ(L"script", parser.GetTextData());
@@ -547,9 +518,7 @@ TEST(CFX_XMLParserTest, BadElementClose) {
   const char* input = "</endtag>";
 
   auto stream = MakeProxy(input);
-  auto root = pdfium::MakeUnique<CFX_XMLElement>(L"ROOT");
-
-  CFX_XMLTestParser parser(root.get(), stream);
+  CFX_XMLTestParser parser(stream);
   ASSERT_EQ(FX_XmlSyntaxResult::Error, parser.DoSyntaxParse());
 }
 
@@ -557,9 +526,7 @@ TEST(CFX_XMLParserTest, DoubleElementClose) {
   const char* input = "<p></p></p>";
 
   auto stream = MakeProxy(input);
-  auto root = pdfium::MakeUnique<CFX_XMLElement>(L"ROOT");
-
-  CFX_XMLTestParser parser(root.get(), stream);
+  CFX_XMLTestParser parser(stream);
   ASSERT_EQ(FX_XmlSyntaxResult::ElementOpen, parser.DoSyntaxParse());
   ASSERT_EQ(FX_XmlSyntaxResult::TagName, parser.DoSyntaxParse());
   ASSERT_EQ(L"p", parser.GetTextData());
@@ -570,6 +537,26 @@ TEST(CFX_XMLParserTest, DoubleElementClose) {
   ASSERT_EQ(FX_XmlSyntaxResult::Error, parser.DoSyntaxParse());
 }
 
+TEST(CFX_XMLParserTest, ParseInstruction) {
+  const char* input =
+      "<?originalXFAVersion http://www.xfa.org/schema/xfa-template/3.3/ ?>"
+      "<form></form>";
+
+  auto stream = MakeProxy(input);
+  CFX_XMLTestParser parser(stream);
+
+  auto doc = parser.Parse();
+  ASSERT_TRUE(doc.get() != nullptr);
+
+  CFX_XMLElement* root = doc->GetRoot();
+  ASSERT_TRUE(root->GetFirstChild() != nullptr);
+  ASSERT_EQ(FX_XMLNODE_Instruction, root->GetFirstChild()->GetType());
+
+  CFX_XMLInstruction* instruction =
+      static_cast<CFX_XMLInstruction*>(root->GetFirstChild());
+  EXPECT_TRUE(instruction->IsOriginalXFAVersion());
+}
+
 TEST(CFX_XMLParserTest, BadEntity) {
   const char* input =
       "<script>"
@@ -577,9 +564,7 @@ TEST(CFX_XMLParserTest, BadEntity) {
       "</script>";
 
   auto stream = MakeProxy(input);
-  auto root = pdfium::MakeUnique<CFX_XMLElement>(L"ROOT");
-
-  CFX_XMLTestParser parser(root.get(), stream);
+  CFX_XMLTestParser parser(stream);
   ASSERT_EQ(FX_XmlSyntaxResult::ElementOpen, parser.DoSyntaxParse());
   ASSERT_EQ(FX_XmlSyntaxResult::TagName, parser.DoSyntaxParse());
   ASSERT_EQ(L"script", parser.GetTextData());
diff --git a/core/fxcrt/xml/cfx_xmltext.cpp b/core/fxcrt/xml/cfx_xmltext.cpp
index 2c324be1c9..73f0477482 100644
--- a/core/fxcrt/xml/cfx_xmltext.cpp
+++ b/core/fxcrt/xml/cfx_xmltext.cpp
@@ -6,6 +6,7 @@
 
 #include "core/fxcrt/xml/cfx_xmltext.h"
 
+#include "core/fxcrt/xml/cfx_xmldocument.h"
 #include "third_party/base/ptr_util.h"
 
 CFX_XMLText::CFX_XMLText(const WideString& wsText)
@@ -17,8 +18,8 @@ FX_XMLNODETYPE CFX_XMLText::GetType() const {
   return FX_XMLNODE_Text;
 }
 
-std::unique_ptr<CFX_XMLNode> CFX_XMLText::Clone() {
-  return pdfium::MakeUnique<CFX_XMLText>(m_wsText);
+CFX_XMLNode* CFX_XMLText::Clone(CFX_XMLDocument* doc) {
+  return doc->CreateNode<CFX_XMLText>(m_wsText);
 }
 
 void CFX_XMLText::Save(const RetainPtr<IFX_SeekableWriteStream>& pXMLStream) {
diff --git a/core/fxcrt/xml/cfx_xmltext.h b/core/fxcrt/xml/cfx_xmltext.h
index cc9c71d01c..c5c168059d 100644
--- a/core/fxcrt/xml/cfx_xmltext.h
+++ b/core/fxcrt/xml/cfx_xmltext.h
@@ -12,6 +12,8 @@
 #include "core/fxcrt/fx_string.h"
 #include "core/fxcrt/xml/cfx_xmlnode.h"
 
+class CFX_XMLDocument;
+
 class CFX_XMLText : public CFX_XMLNode {
  public:
   explicit CFX_XMLText(const WideString& wsText);
@@ -19,7 +21,7 @@ class CFX_XMLText : public CFX_XMLNode {
 
   // CFX_XMLNode
   FX_XMLNODETYPE GetType() const override;
-  std::unique_ptr<CFX_XMLNode> Clone() override;
+  CFX_XMLNode* Clone(CFX_XMLDocument* doc) override;
   void Save(const RetainPtr<IFX_SeekableWriteStream>& pXMLStream) override;
 
   WideString GetText() const { return m_wsText; }
diff --git a/core/fxcrt/xml/cfx_xmltext_unittest.cpp b/core/fxcrt/xml/cfx_xmltext_unittest.cpp
index ab977e9546..6e53f66612 100644
--- a/core/fxcrt/xml/cfx_xmltext_unittest.cpp
+++ b/core/fxcrt/xml/cfx_xmltext_unittest.cpp
@@ -3,6 +3,7 @@
 // found in the LICENSE file.
 
 #include "core/fxcrt/xml/cfx_xmltext.h"
+#include "core/fxcrt/xml/cfx_xmldocument.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "testing/string_write_stream.h"
 #include "testing/test_support.h"
@@ -18,11 +19,13 @@ TEST(CFX_XMLTextTest, GetText) {
 }
 
 TEST(CFX_XMLTextTest, Clone) {
+  CFX_XMLDocument doc;
+
   CFX_XMLText data(L"My Data");
-  auto clone = data.Clone();
+  CFX_XMLNode* clone = data.Clone(&doc);
   EXPECT_TRUE(clone != nullptr);
   ASSERT_EQ(FX_XMLNODE_Text, clone->GetType());
-  EXPECT_EQ(L"My Data", static_cast<CFX_XMLText*>(clone.get())->GetText());
+  EXPECT_EQ(L"My Data", static_cast<CFX_XMLText*>(clone)->GetText());
 }
 
 TEST(CFX_XMLTextTest, Save) {