Remove CPDF_Parser::GetObjectGenNum().

It is not called anywhere.

Change-Id: I8c9939c0f15e867d09faba847d3f91b370e1aa17
Reviewed-on: https://pdfium-review.googlesource.com/c/pdfium/+/63410
Auto-Submit: Tom Sepez <tsepez@chromium.org>
Commit-Queue: Lei Zhang <thestig@chromium.org>
Reviewed-by: Lei Zhang <thestig@chromium.org>

core/fpdfapi/parser/cpdf_parser.cpp

diff --git a/core/fpdfapi/parser/cpdf_parser.cpp b/core/fpdfapi/parser/cpdf_parser.cpp
index 6ce5853..e4ac195 100644
--- a/core/fpdfapi/parser/cpdf_parser.cpp
+++ b/core/fpdfapi/parser/cpdf_parser.cpp
@@ -91,12 +91,6 @@
   return info ? info->type : ObjectType::kFree;
 }
 
-uint16_t CPDF_Parser::GetObjectGenNum(uint32_t objnum) const {
-  ASSERT(IsValidObjectNumber(objnum));
-  const auto* info = m_CrossRefTable->GetObjectInfo(objnum);
-  return (info && info->type == ObjectType::kNormal) ? info->gennum : 0;
-}
-
 bool CPDF_Parser::IsObjectFreeOrNull(uint32_t objnum) const {
   switch (GetObjectType(objnum)) {
     case ObjectType::kFree:

core/fpdfapi/parser/cpdf_parser.h

diff --git a/core/fpdfapi/parser/cpdf_parser.h b/core/fpdfapi/parser/cpdf_parser.h
index 3befd03..30d08ea 100644
--- a/core/fpdfapi/parser/cpdf_parser.h
+++ b/core/fpdfapi/parser/cpdf_parser.h
@@ -88,7 +88,6 @@
   uint32_t GetLastObjNum() const;
   bool IsValidObjectNumber(uint32_t objnum) const;
   FX_FILESIZE GetObjectPositionOrZero(uint32_t objnum) const;
-  uint16_t GetObjectGenNum(uint32_t objnum) const;
   bool IsObjectFreeOrNull(uint32_t objnum) const;
   const RetainPtr<CPDF_SecurityHandler>& GetSecurityHandler() const {
     return m_pSecurityHandler;