New GC APIs, try 2.

include/v8-profiler.h

Index: include/v8-profiler.h
diff --git a/include/v8-profiler.h b/include/v8-profiler.h
index 5c5c7a946c91014b22ba127cae2c4785ddfde8fb..bc50b6f42bcc36779d1c4c4eeeb65e16824a3586 100644
--- a/include/v8-profiler.h
+++ b/include/v8-profiler.h
@@ -554,6 +554,11 @@ class V8EXPORT HeapProfiler {
   /** Returns memory used for profiler internal data and snapshots. */
   size_t GetProfilerMemorySize();
 
+  /**
+   * Sets a RetainedObjectInfo for an object group (see V8::SetObjectGroupId).
+   */
+  void SetRetainedObjectInfo(UniqueId id, RetainedObjectInfo* info);
+
  private:
   HeapProfiler();
   ~HeapProfiler();