Oilpan: Added gyp flag to dump points-to graph information from the Blink GC plugin.

Source/heap/Heap.h

 /*
  * Copyright (C) 2013 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 1054 matching lines @@
 #if COMPILER(CLANG) && !defined(ADDRESS_SANITIZER)
 #define STACK_ALLOCATED()                                       \
     private:                                                    \
         __attribute__((annotate("blink_stack_allocated")))      \
         void* operator new(size_t) = delete;                    \
         void* operator new(size_t, NotNullTag, void*) = delete; \
         void* operator new(size_t, void*) = delete;
 
 #define GC_PLUGIN_IGNORE(bug)                           \
     __attribute__((annotate("blink_gc_plugin_ignore")))
+
+#define GC_PLUGIN_IGNORE_CYCLE                                  \
+    __attribute__((annotate("blink_gc_plugin_ignore_cycle")))
 #else
 #define STACK_ALLOCATED() DISALLOW_ALLOCATION()
 #define GC_PLUGIN_IGNORE(bug)
+#define GC_PLUGIN_IGNORE_CYCLE
 #endif
 
 NO_SANITIZE_ADDRESS
 void HeapObjectHeader::checkHeader() const
 {
     ASSERT(m_magic == magic);
 }
 
 Address HeapObjectHeader::payload()
 {
@@ skipping 646 matching lines @@
 // to export. This forces it to export all the methods from ThreadHeap.
 template<> void ThreadHeap<FinalizedHeapObjectHeader>::addPageToHeap(const GCInfo*);
 template<> void ThreadHeap<HeapObjectHeader>::addPageToHeap(const GCInfo*);
 extern template class HEAP_EXPORT ThreadHeap<FinalizedHeapObjectHeader>;
 extern template class HEAP_EXPORT ThreadHeap<HeapObjectHeader>;
 #endif
 
 }
 
 #endif // Heap_h