Add 'address' vm service message that finds heap objects.

runtime/vm/heap.h

 // Copyright (c) 2012, 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.
 
 #ifndef VM_HEAP_H_
 #define VM_HEAP_H_
 
 #include "platform/assert.h"
 #include "vm/allocation.h"
 #include "vm/flags.h"
@@ skipping 116 matching lines @@
   void IterateNewObjects(ObjectVisitor* visitor);
   void IterateOldObjects(ObjectVisitor* visitor);
 
   // Find an object by visiting all pointers in the specified heap space,
   // the 'visitor' is used to determine if an object is found or not.
   // The 'visitor' function should be set up to return true if the
   // object is found, traversal through the heap space stops at that
   // point.
   // The 'visitor' function should return false if the object is not found,
   // traversal through the heap space continues.
-  RawInstructions* FindObjectInCodeSpace(FindObjectVisitor* visitor);
-  RawInstructions* FindObjectInStubCodeSpace(FindObjectVisitor* visitor);
+  // Returns null object if nothing is found. Must be called within a NoGCScope.
+  RawInstructions* FindObjectInCodeSpace(FindObjectVisitor* visitor) const;
   RawObject* FindOldObject(FindObjectVisitor* visitor) const;
+  RawObject* FindNewObject(FindObjectVisitor* visitor) const;
+  RawObject* FindObject(FindObjectVisitor* visitor) const;
 
   void CollectGarbage(Space space);
   void CollectGarbage(Space space, ApiCallbacks api_callbacks);
   void CollectAllGarbage();
 
   // Enables growth control on the page space heaps.  This should be
   // called before any user code is executed.
   void EnableGrowthControl() { SetGrowthControlState(true); }
   void DisableGrowthControl() { SetGrowthControlState(false); }
   void SetGrowthControlState(bool state);
@@ skipping 186 matching lines @@
   NoHeapGrowthControlScope();
   ~NoHeapGrowthControlScope();
  private:
   bool current_growth_controller_state_;
   DISALLOW_COPY_AND_ASSIGN(NoHeapGrowthControlScope);
 };
 
 }  // namespace dart
 
 #endif  // VM_HEAP_H_