Add field names to Code, ConsString, and JSGlobalPropertyCell in heap snapshot.

src/profile-generator.h

 // Copyright 2011 the V8 project authors. 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
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 968 matching lines @@
   void ExtractReferences(HeapObject* obj);
   void ExtractJSGlobalProxy(JSGlobalProxy* proxy);
   void ExtractJSObject(HeapEntry* entry, JSObject* js_obj);
   void ExtractString(HeapEntry* entry, String* obj);
   void ExtractContext(HeapEntry* entry, Context* context);
   void ExtractMap(HeapEntry* entry, Map* map);
   void ExtractSharedFunctionInfo(HeapEntry* entry, SharedFunctionInfo* shared);
   void ExtractScript(HeapEntry* entry, Script* script);
   void ExtractCodeCache(HeapEntry* entry, CodeCache* code_cache);
   void ExtractCode(HeapEntry* entry, Code* code);
+  void ExtractJSGlobalPropertyCell(HeapEntry* entry,
+                                   JSGlobalPropertyCell* cell);
   void ExtractClosureReferences(JSObject* js_obj, HeapEntry* entry);
   void ExtractPropertyReferences(JSObject* js_obj, HeapEntry* entry);
   void ExtractElementReferences(JSObject* js_obj, HeapEntry* entry);
   void ExtractInternalReferences(JSObject* js_obj, HeapEntry* entry);
   bool IsEssentialObject(Object* object);
   void SetClosureReference(HeapObject* parent_obj,
                            HeapEntry* parent,
                            String* reference_name,
                            Object* child);
   void SetNativeBindReference(HeapObject* parent_obj,
@@ skipping 207 matching lines @@
 
   friend class HeapSnapshotJSONSerializerEnumerator;
   friend class HeapSnapshotJSONSerializerIterator;
 
   DISALLOW_COPY_AND_ASSIGN(HeapSnapshotJSONSerializer);
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_PROFILE_GENERATOR_H_