Fix memory leaking on ClosePage.chromium/2862

CFX_FontCache refactoring:
  after this CL: Only one global CFX_FontCache used. Any cached items from it, are released, when its are not used.

BUG=79367,48791

The fonts was not cleared after unloading pages.

Test pdf:

http://www.nasa.gov/pdf/750614main_NASA_FY_2014_Budget_Estimates-508.pdf

For this file, we have ~5 fonts per page, which equal ~1 Mb per page.
In this PDF we have 670 pages, as result after slow scrolling(reading) full document we have ~600 Mb fonts data in memory.

memory usage of PDF Plugin:
  before this CL: ~660 Mb
  after this CL: ~100 Mb

Review-Url: https://codereview.chromium.org/2158023002

1 files changed, 14 insertions, 7 deletions

diff --git a/core/fpdfapi/fpdf_page/fpdf_page_doc.cpp b/core/fpdfapi/fpdf_page/fpdf_page_doc.cpp
index 9e586e326f..f83d6fa613 100644
--- a/core/fpdfapi/fpdf_page/fpdf_page_doc.cpp
+++ b/core/fpdfapi/fpdf_page/fpdf_page_doc.cpp
@@ -214,9 +214,10 @@ void CPDF_DocPageData::ReleaseFont(const CPDF_Dictionary* pFontDict) {
     return;
 
   pFontData->RemoveRef();
-  if (pFontData->use_count() != 0)
+  if (pFontData->use_count() > 1)
     return;
 
+  // We have font data only in m_FontMap cache. Clean it.
   pFontData->clear();
 }
 
@@ -330,9 +331,10 @@ void CPDF_DocPageData::ReleaseColorSpace(const CPDF_Object* pColorSpace) {
     return;
 
   pCountedColorSpace->RemoveRef();
-  if (pCountedColorSpace->use_count() != 0)
+  if (pCountedColorSpace->use_count() > 1)
     return;
 
+  // We have item only in m_ColorSpaceMap cache. Clean it.
   pCountedColorSpace->get()->ReleaseCS();
   pCountedColorSpace->reset(nullptr);
 }
@@ -391,9 +393,10 @@ void CPDF_DocPageData::ReleasePattern(const CPDF_Object* pPatternObj) {
     return;
 
   pPattern->RemoveRef();
-  if (pPattern->use_count() != 0)
+  if (pPattern->use_count() > 1)
     return;
 
+  // We have item only in m_PatternMap cache. Clean it.
   pPattern->clear();
 }
 
@@ -429,9 +432,10 @@ void CPDF_DocPageData::ReleaseImage(const CPDF_Object* pImageStream) {
     return;
 
   pCountedImage->RemoveRef();
-  if (pCountedImage->use_count() != 0)
+  if (pCountedImage->use_count() > 1)
     return;
 
+  // We have item only in m_ImageMap cache. Clean it.
   delete pCountedImage->get();
   delete pCountedImage;
   m_ImageMap.erase(it);
@@ -454,7 +458,8 @@ CPDF_IccProfile* CPDF_DocPageData::GetIccProfile(
   auto hash_it = m_HashProfileMap.find(bsDigest);
   if (hash_it != m_HashProfileMap.end()) {
     auto it_copied_stream = m_IccProfileMap.find(hash_it->second);
-    return it_copied_stream->second->AddRef();
+    if (it_copied_stream != m_IccProfileMap.end())
+      return it_copied_stream->second->AddRef();
   }
   CPDF_IccProfile* pProfile =
       new CPDF_IccProfile(stream.GetData(), stream.GetSize());
@@ -473,7 +478,8 @@ void CPDF_DocPageData::ReleaseIccProfile(const CPDF_IccProfile* pIccProfile) {
       continue;
 
     profile->RemoveRef();
-    if (profile->use_count() == 0) {
+    if (profile->use_count() == 1) {
+      // We have item only in m_IccProfileMap cache. Clean it.
       delete profile->get();
       delete profile;
       m_IccProfileMap.erase(it);
@@ -518,9 +524,10 @@ void CPDF_DocPageData::ReleaseFontFileStreamAcc(
     return;
 
   pCountedStream->RemoveRef();
-  if (pCountedStream->use_count() != 0)
+  if (pCountedStream->use_count() > 1)
     return;
 
+  // We have item only in m_FontFileMap cache. Clean it.
   delete pCountedStream->get();
   delete pCountedStream;
   m_FontFileMap.erase(it);