Revert "Change CFX_XML Save to take a write stream"

This reverts commit 9a3a7709103a872037dcea1f3cf0b7785a3da191.

Reason for revert: Gerrit did not do what I expected....

Original change's description:
> Change CFX_XML Save to take a write stream
> 
> This CL changes CFX_XML to use an IFX_SeekableWriteStream instead of the more
> generic IFX_SeekableStream.
> 
> Change-Id: I6e4def380c43eca755d91ad5cb6146c2dfdaee10
> Reviewed-on: https://pdfium-review.googlesource.com/30877
> Commit-Queue: dsinclair <dsinclair@chromium.org>
> Reviewed-by: Tom Sepez <tsepez@chromium.org>

TBR=tsepez@chromium.org,dsinclair@chromium.org,hnakashima@chromium.org

Change-Id: I137e53bf93285b88ade6832dedefca66e3b61e13
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://pdfium-review.googlesource.com/31211
Reviewed-by: dsinclair <dsinclair@chromium.org>
Commit-Queue: dsinclair <dsinclair@chromium.org>

1 files changed, 6 insertions, 4 deletions

diff --git a/core/fpdfdoc/cpdf_metadata.cpp b/core/fpdfdoc/cpdf_metadata.cpp
index c928952dca..161fc93edd 100644
--- a/core/fpdfdoc/cpdf_metadata.cpp
+++ b/core/fpdfdoc/cpdf_metadata.cpp
@@ -19,11 +19,12 @@ void CheckForSharedFormInternal(CFX_XMLElement* element,
                                 std::vector<UnsupportedFeature>* unsupported) {
   WideString attr = element->GetAttribute(L"xmlns:adhocwf");
   if (attr == L"http://ns.adobe.com/AcrobatAdhocWorkflow/1.0/") {
-    for (const auto& child : *element) {
+    for (const auto* child = element->GetFirstChild(); child;
+         child = child->GetNextSibling()) {
       if (child->GetType() != FX_XMLNODE_Element)
         continue;
 
-      const auto* child_elem = static_cast<const CFX_XMLElement*>(child.get());
+      const auto* child_elem = static_cast<const CFX_XMLElement*>(child);
       if (child_elem->GetName() != L"adhocwf:workflowType")
         continue;
 
@@ -45,11 +46,12 @@ void CheckForSharedFormInternal(CFX_XMLElement* element,
     }
   }
 
-  for (const auto& child : *element) {
+  for (auto* child = element->GetFirstChild(); child;
+       child = child->GetNextSibling()) {
     if (child->GetType() != FX_XMLNODE_Element)
       continue;
 
-    CheckForSharedFormInternal(static_cast<CFX_XMLElement*>(child.get()),
+    CheckForSharedFormInternal(static_cast<CFX_XMLElement*>(child),
                                unsupported);
   }
 }