Revert of Fix loading page using hint tables. (patchset #5 id:80001 of https://codereview.chromium.org/2437773003/ )

Reason for revert:
CPDF_DataAvail::IsPageAvail is causing crashes.

BUG=chromium:658168, chromium:658170

Original issue's description:
> Fix loading page using hint tables.
>
> When linearized document have hint table,
> The FPDFAvail_IsPageAvail return true, but
> FPDF_LoadPage return nullptr, for non first pages.
>
> This happens, bacause document not use hint tables, to load page.
>
> To fix this, I force save the page's ObjNum in document.
>
> R=npm, dsinclair
>
> Committed: https://pdfium.googlesource.com/pdfium/+/ef38283688c1ee7c08bcf4204cfb78e09c039782

TBR=dsinclair@chromium.org,tsepez@chromium.org,thestig@chromium.org,art-snake@yandex-team.ru
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true

Review-Url: https://chromiumcodereview.appspot.com/2442663005

3 files changed, 2 insertions, 55 deletions

diff --git a/core/fpdfapi/parser/cpdf_data_avail.cpp b/core/fpdfapi/parser/cpdf_data_avail.cpp
index e52d0611f9..e23aa8ecfb 100644
--- a/core/fpdfapi/parser/cpdf_data_avail.cpp
+++ b/core/fpdfapi/parser/cpdf_data_avail.cpp
@@ -1625,8 +1625,6 @@ CPDF_DataAvail::DocAvailStatus CPDF_DataAvail::IsPageAvail(
       nResult = m_pHintTables->CheckPage(dwPage, pHints);
       if (nResult != DataAvailable)
         return nResult;
-      // We should say to the document, which object is the page.
-      m_pDocument->SetPageObjNum(dwPage, GetPage(dwPage)->GetObjNum());
       m_pagesLoadState.insert(dwPage);
       return DataAvailable;
     }
@@ -1765,18 +1763,11 @@ CPDF_Dictionary* CPDF_DataAvail::GetPage(int index) {
       uint32_t dwObjNum = 0;
       bool bPagePosGot = m_pHintTables->GetPagePos(index, &szPageStartPos,
                                                    &szPageLength, &dwObjNum);
-      if (!dwObjNum)
-        return nullptr;
-      // Page object already can be parsed in document.
-      CPDF_Object* pPageDict = m_pDocument->GetIndirectObject(dwObjNum);
-      if (pPageDict)
-        return pPageDict->GetDict();
-
       if (!bPagePosGot)
         return nullptr;
 
       m_syntaxParser.InitParser(m_pFileRead, (uint32_t)szPageStartPos);
-      pPageDict = ParseIndirectObjectAt(0, dwObjNum, m_pDocument);
+      CPDF_Object* pPageDict = ParseIndirectObjectAt(0, dwObjNum, m_pDocument);
       if (!pPageDict)
         return nullptr;
 
diff --git a/core/fpdfapi/parser/cpdf_document.cpp b/core/fpdfapi/parser/cpdf_document.cpp
index 5f64c14d31..c5f64a790c 100644
--- a/core/fpdfapi/parser/cpdf_document.cpp
+++ b/core/fpdfapi/parser/cpdf_document.cpp
@@ -425,9 +425,7 @@ CPDF_Document::CPDF_Document(std::unique_ptr<CPDF_Parser> pParser)
 
 CPDF_Document::~CPDF_Document() {
   delete m_pDocPage;
-  if (CPDF_ModuleMgr::Get()->GetPageModule()) {
-    CPDF_ModuleMgr::Get()->GetPageModule()->ClearStockFont(this);
-  }
+  CPDF_ModuleMgr::Get()->GetPageModule()->ClearStockFont(this);
   m_pByteStringPool.DeleteObject();  // Make weak.
 }
 
diff --git a/core/fpdfapi/parser/cpdf_document_unittest.cpp b/core/fpdfapi/parser/cpdf_document_unittest.cpp
deleted file mode 100644
index 128b8d91c4..0000000000
--- a/core/fpdfapi/parser/cpdf_document_unittest.cpp
+++ /dev/null
@@ -1,42 +0,0 @@
-// Copyright 2016 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/fpdfapi/parser/cpdf_document.h"
-
-#include <memory>
-
-#include "core/fpdfapi/parser/cpdf_parser.h"
-#include "core/fpdfapi/parser/cpdf_dictionary.h"
-#include "core/fxcrt/fx_memory.h"
-#include "testing/gtest/include/gtest/gtest.h"
-
-namespace {
-
-using ScopedDictionary =
-    std::unique_ptr<CPDF_Dictionary, ReleaseDeleter<CPDF_Dictionary>>;
-
-}  // namespace
-
-TEST(cpdf_document, UseCachedPageObjNumIfHaveNotPagesDict) {
-  // ObjNum can be added in CPDF_DataAvail::IsPageAvail, and PagesDict
-  // can be not exists in this case.
-  // (case, when hint table is used to page check in CPDF_DataAvail).
-  std::unique_ptr<CPDF_Parser> parser(new CPDF_Parser());
-  CPDF_Document document(std::move(parser));
-  ScopedDictionary dict(new CPDF_Dictionary());
-  const int page_count = 100;
-  dict->SetIntegerFor("N", page_count);
-  document.LoadLinearizedDoc(dict.get());
-  ASSERT_EQ(page_count, document.GetPageCount());
-  CPDF_Object* page_stub = new CPDF_Dictionary();
-  const uint32_t obj_num = document.AddIndirectObject(page_stub);
-  const int test_page_num = 33;
-
-  EXPECT_FALSE(document.IsPageLoaded(test_page_num));
-  EXPECT_EQ(nullptr, document.GetPage(test_page_num));
-
-  document.SetPageObjNum(test_page_num, obj_num);
-  EXPECT_TRUE(document.IsPageLoaded(test_page_num));
-  EXPECT_EQ(page_stub, document.GetPage(test_page_num));
-}