Add v8::HeapGraphNode::GetHeapValue method.

src/api.cc

Index: src/api.cc
diff --git a/src/api.cc b/src/api.cc
index 6a58417879c438d84d85ae26424f6c421e5b395d..7ae01d14e4021ea450d1e21c561b723a199e7ce2 100644
--- a/src/api.cc
+++ b/src/api.cc
@@ -5811,6 +5811,16 @@ const HeapGraphNode* HeapGraphNode::GetDominatorNode() const {
 }
 
 
+v8::Handle<v8::Value> HeapGraphNode::GetHeapValue() const {
+  i::Isolate* isolate = i::Isolate::Current();
+  IsDeadCheck(isolate, "v8::HeapGraphNode::GetHeapValue");
+  i::Handle<i::HeapObject> object = ToInternal(this)->GetHeapObject();
+  return v8::Handle<Value>(!object.is_null() ?
+                           ToApi<Value>(object) : ToApi<Value>(
+                               isolate->factory()->undefined_value()));
+}
+
+
 static i::HeapSnapshot* ToInternal(const HeapSnapshot* snapshot) {
   return const_cast<i::HeapSnapshot*>(
       reinterpret_cast<const i::HeapSnapshot*>(snapshot));