Introduce EmbedderHeapTracer

src/global-handles.h

 // Copyright 2011 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef V8_GLOBAL_HANDLES_H_
 #define V8_GLOBAL_HANDLES_H_
 
 #include "include/v8.h"
 #include "include/v8-profiler.h"
 
@@ skipping 130 matching lines @@
   // in the callback by using the location() of the handle.
   static void MakeWeak(Object** location, void* parameter,
                        WeakCallback weak_callback);
 
   // It would be nice to template this one, but it's really hard to get
   // the template instantiator to work right if you do.
   static void MakeWeak(Object** location, void* parameter,
                        WeakCallbackInfo<void>::Callback weak_callback,
                        v8::WeakCallbackType type);
 
+  static void AddObjectToMarkingDeque(Object** object, Isolate* isolate);
+
   void RecordStats(HeapStats* stats);
 
   // Returns the current number of weak handles.
   int NumberOfWeakHandles();
 
   // Returns the current number of weak handles to global objects.
   // These handles are also included in NumberOfWeakHandles().
   int NumberOfGlobalObjectWeakHandles();
 
   // Returns the current number of handles to global objects.
@@ skipping 294 matching lines @@
   int singleton_handles_[NUMBER_OF_SINGLETON_HANDLES];
 
   DISALLOW_COPY_AND_ASSIGN(EternalHandles);
 };
 
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_GLOBAL_HANDLES_H_