Restore frame validation (fixes to CL faaf60801f72).

runtime/vm/isolate.cc

 // Copyright (c) 2013, 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/isolate.h"
 
 #include "include/dart_api.h"
 #include "platform/assert.h"
 #include "platform/json.h"
 #include "vm/code_observers.h"
@@ skipping 1609 matching lines @@
       reinterpret_cast<RawObject**>(&deoptimized_code_array_));
 
   // Visit objects in the debugger.
   debugger()->VisitObjectPointers(visitor);
 
   // Visit objects that are being used for deoptimization.
   if (deopt_context() != NULL) {
     deopt_context()->VisitObjectPointers(visitor);
   }
 
-  // Visit objects in thread registry (e.g., handles in zones).
-  thread_registry()->VisitObjectPointers(visitor);
+  // Visit objects in thread registry (e.g., Dart stack, handles in zones).
+  thread_registry()->VisitObjectPointers(visitor, validate_frames);
 }
 
 
 void Isolate::VisitWeakPersistentHandles(HandleVisitor* visitor,
                                          bool visit_prologue_weak_handles) {
   if (api_state() != NULL) {
     api_state()->VisitWeakHandles(visitor, visit_prologue_weak_handles);
   }
 }
 
@@ skipping 518 matching lines @@
                            serialized_message_, serialized_message_len_);
 }
 
 
 void IsolateSpawnState::Cleanup() {
   SwitchIsolateScope switch_scope(I);
   Dart::ShutdownIsolate();
 }
 
 }  // namespace dart