Fix a leak with FPDFPageObj_NewImgeObj().

core/fpdfapi/fpdf_page/fpdf_page_doc.cpp

Index: core/fpdfapi/fpdf_page/fpdf_page_doc.cpp
diff --git a/core/fpdfapi/fpdf_page/fpdf_page_doc.cpp b/core/fpdfapi/fpdf_page/fpdf_page_doc.cpp
index 059679a8cda1f3d7284c6278e73b074697a2b9b7..7d842a2d53b4b5840590d9ad5310deba20d26efd 100644
--- a/core/fpdfapi/fpdf_page/fpdf_page_doc.cpp
+++ b/core/fpdfapi/fpdf_page/fpdf_page_doc.cpp
@@ -414,29 +414,30 @@ CPDF_Image* CPDF_DocPageData::GetImage(CPDF_Object* pImageStream) {
   return pCountedImage->AddRef();
 }
 
-void CPDF_DocPageData::ReleaseImage(const CPDF_Object* pImageStream) {
+bool CPDF_DocPageData::ReleaseImage(const CPDF_Object* pImageStream) {
   if (!pImageStream)
-    return;
+    return false;
 
   uint32_t dwObjNum = pImageStream->GetObjNum();
   if (!dwObjNum)
-    return;
+    return false;
 
   auto it = m_ImageMap.find(dwObjNum);
   if (it == m_ImageMap.end())
-    return;
+    return false;
 
   CPDF_CountedImage* pCountedImage = it->second;
   if (!pCountedImage)
-    return;
+    return false;
 
   pCountedImage->RemoveRef();
   if (pCountedImage->use_count() != 0)
-    return;
+    return false;
 
   delete pCountedImage->get();
   delete pCountedImage;
   m_ImageMap.erase(it);
+  return true;
 }
 
 CPDF_IccProfile* CPDF_DocPageData::GetIccProfile(