Make ObjectGraph a StackResource.

runtime/vm/object_graph.cc

 // Copyright (c) 2014, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/object_graph.h"
 
 #include "vm/dart.h"
 #include "vm/growable_array.h"
 #include "vm/isolate.h"
 #include "vm/object.h"
@@ skipping 95 matching lines @@
   static void UnmarkAll(Isolate* isolate) {
     Unmarker unmarker(isolate);
     isolate->heap()->IterateObjects(&unmarker);
   }
 
  private:
   DISALLOW_COPY_AND_ASSIGN(Unmarker);
 };
 
 
-ObjectGraph::ObjectGraph(Isolate* isolate) : isolate_(isolate) {
+ObjectGraph::ObjectGraph(Isolate* isolate)
+    : StackResource(isolate), isolate_(isolate) {
   // The VM isolate has all its objects pre-marked, so iterating over it
   // would be a no-op.
   ASSERT(isolate_ != Dart::vm_isolate());
   isolate_->heap()->WriteProtectCode(false);
 }
 
 
 ObjectGraph::~ObjectGraph() {
   isolate_->heap()->WriteProtectCode(true);
 }
@@ skipping 13 matching lines @@
   NoGCScope no_gc_scope_;
   Stack stack(isolate_);
   RawObject* root_raw = root.raw();
   stack.VisitPointer(&root_raw);
   stack.TraverseGraph(visitor);
   // TODO(koda): Optimize if we only visited a small subgraph.
   Unmarker::UnmarkAll(isolate_);
 }
 
 }  // namespace dart