Revert of Remove CPDF_Object::Release() in favor of direct delete (patchset #11 id:200001 of https://codereview.chromium.org/2384883003/ )

Reason for revert:
Looks like it's blocking the roll.

https://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_compile_dbg_ng/builds/186619

Original issue's description:
> Remove CPDF_Object::Release() in favor of direct delete
>
> Follow-on once we prove Release always deletes in previous CL.
>
> Committed: https://pdfium.googlesource.com/pdfium/+/4de3d095c9d9e961f93750cf1ebd489fd515be12

TBR=thestig@chromium.org,tsepez@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true

Review-Url: https://codereview.chromium.org/2478253002

1 files changed, 34 insertions, 20 deletions

diff --git a/core/fpdfapi/parser/cpdf_parser.cpp b/core/fpdfapi/parser/cpdf_parser.cpp
index da95cc5f24..cff0f77b32 100644
--- a/core/fpdfapi/parser/cpdf_parser.cpp
+++ b/core/fpdfapi/parser/cpdf_parser.cpp
@@ -61,7 +61,9 @@ CPDF_Parser::CPDF_Parser()
 }
 
 CPDF_Parser::~CPDF_Parser() {
-  delete m_pTrailer;
+  if (m_pTrailer)
+    m_pTrailer->Release();
+
   ReleaseEncryptHandler();
   SetEncryptDictionary(nullptr);
 
@@ -70,10 +72,13 @@ CPDF_Parser::~CPDF_Parser() {
     m_pSyntax->m_pFileAccess = nullptr;
   }
 
-  for (CPDF_Dictionary* trailer : m_Trailers)
-    delete trailer;
+  for (CPDF_Dictionary* trailer : m_Trailers) {
+    if (trailer)
+      trailer->Release();
+  }
 
-  delete m_pLinearized;
+  if (m_pLinearized)
+    m_pLinearized->Release();
 }
 
 uint32_t CPDF_Parser::GetLastObjNum() const {
@@ -352,7 +357,8 @@ bool CPDF_Parser::LoadAllCrossRefV4(FX_FILESIZE xrefpos) {
     CrossRefList.insert(CrossRefList.begin(), xrefpos);
     LoadCrossRefV4(xrefpos, 0, true);
 
-    std::unique_ptr<CPDF_Dictionary> pDict(LoadTrailerV4());
+    std::unique_ptr<CPDF_Dictionary, ReleaseDeleter<CPDF_Dictionary>> pDict(
+        LoadTrailerV4());
     if (!pDict)
       return false;
 
@@ -406,7 +412,8 @@ bool CPDF_Parser::LoadLinearizedAllCrossRefV4(FX_FILESIZE xrefpos,
     CrossRefList.insert(CrossRefList.begin(), xrefpos);
     LoadCrossRefV4(xrefpos, 0, true);
 
-    std::unique_ptr<CPDF_Dictionary> pDict(LoadTrailerV4());
+    std::unique_ptr<CPDF_Dictionary, ReleaseDeleter<CPDF_Dictionary>> pDict(
+        LoadTrailerV4());
     if (!pDict)
       return false;
 
@@ -583,14 +590,18 @@ bool CPDF_Parser::LoadAllCrossRefV5(FX_FILESIZE xrefpos) {
 bool CPDF_Parser::RebuildCrossRef() {
   m_ObjectInfo.clear();
   m_SortedOffset.clear();
-  delete m_pTrailer;
-  m_pTrailer = nullptr;
+  if (m_pTrailer) {
+    m_pTrailer->Release();
+    m_pTrailer = nullptr;
+  }
 
   ParserState state = ParserState::kDefault;
+
   int32_t inside_index = 0;
   uint32_t objnum = 0;
   uint32_t gennum = 0;
   int32_t depth = 0;
+
   const uint32_t kBufferSize = 4096;
   std::vector<uint8_t> buffer(kBufferSize);
 
@@ -744,7 +755,8 @@ bool CPDF_Parser::RebuildCrossRef() {
                       CPDF_Object* pRoot = pDict->GetObjectFor("Root");
                       if (pRoot && pRoot->GetDict() &&
                           pRoot->GetDict()->GetObjectFor("Pages")) {
-                        delete m_pTrailer;
+                        if (m_pTrailer)
+                          m_pTrailer->Release();
                         m_pTrailer = ToDictionary(pDict->Clone());
                       }
                     }
@@ -782,7 +794,8 @@ bool CPDF_Parser::RebuildCrossRef() {
                   m_ObjectInfo[objnum].gennum = gennum;
                 }
 
-                delete pObject;
+                if (pObject)
+                  pObject->Release();
               }
               --i;
               state = ParserState::kDefault;
@@ -799,7 +812,7 @@ bool CPDF_Parser::RebuildCrossRef() {
               CPDF_Object* pObj = m_pSyntax->GetObject(m_pDocument, 0, 0, true);
               if (pObj) {
                 if (!pObj->IsDictionary() && !pObj->AsStream()) {
-                  delete pObj;
+                  pObj->Release();
                 } else {
                   CPDF_Stream* pStream = pObj->AsStream();
                   if (CPDF_Dictionary* pTrailer =
@@ -825,11 +838,11 @@ bool CPDF_Parser::RebuildCrossRef() {
                           }
                         }
                       }
-                      delete pObj;
+                      pObj->Release();
                     } else {
                       if (pObj->IsStream()) {
                         m_pTrailer = ToDictionary(pTrailer->Clone());
-                        delete pObj;
+                        pObj->Release();
                       } else {
                         m_pTrailer = pTrailer;
                       }
@@ -846,7 +859,7 @@ bool CPDF_Parser::RebuildCrossRef() {
                       m_pSyntax->RestorePos(dwSavePos);
                     }
                   } else {
-                    delete pObj;
+                    pObj->Release();
                   }
                 }
               }
@@ -1405,7 +1418,7 @@ CPDF_Dictionary* CPDF_Parser::LoadTrailerV4() {
   if (m_pSyntax->GetKeyword() != "trailer")
     return nullptr;
 
-  std::unique_ptr<CPDF_Object> pObj(
+  std::unique_ptr<CPDF_Object, ReleaseDeleter<CPDF_Object>> pObj(
       m_pSyntax->GetObject(m_pDocument, 0, 0, true));
   if (!ToDictionary(pObj.get()))
     return nullptr;
@@ -1457,7 +1470,7 @@ bool CPDF_Parser::IsLinearizedFile(IFX_SeekableReadStream* pFileAccess,
 
     CPDF_Object* pLen = pDict->GetObjectFor("L");
     if (!pLen) {
-      delete m_pLinearized;
+      m_pLinearized->Release();
       m_pLinearized = nullptr;
       return false;
     }
@@ -1473,7 +1486,7 @@ bool CPDF_Parser::IsLinearizedFile(IFX_SeekableReadStream* pFileAccess,
 
     return true;
   }
-  delete m_pLinearized;
+  m_pLinearized->Release();
   m_pLinearized = nullptr;
   return false;
 }
@@ -1582,11 +1595,12 @@ bool CPDF_Parser::LoadLinearizedAllCrossRefV5(FX_FILESIZE xrefpos) {
 CPDF_Parser::Error CPDF_Parser::LoadLinearizedMainXRefTable() {
   uint32_t dwSaveMetadataObjnum = m_pSyntax->m_MetadataObjnum;
   m_pSyntax->m_MetadataObjnum = 0;
+  if (m_pTrailer) {
+    m_pTrailer->Release();
+    m_pTrailer = nullptr;
+  }
 
-  delete m_pTrailer;
-  m_pTrailer = nullptr;
   m_pSyntax->RestorePos(m_LastXRefOffset - m_pSyntax->m_HeaderOffset);
-
   uint8_t ch = 0;
   uint32_t dwCount = 0;
   m_pSyntax->GetNextChar(ch);