Assert that FreeListElement is never wrapped in a handle.

runtime/vm/object.cc

 // 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.
 
 #include "vm/object.h"
 
 #include "include/dart_api.h"
 #include "platform/assert.h"
 #include "vm/assembler.h"
 #include "vm/cpu.h"
@@ skipping 846 matching lines @@
 #if defined(DEBUG)
   Isolate* isolate = Isolate::Current();
   ASSERT(isolate != NULL);
   Class& cls = Class::Handle(isolate, Class::null());
   for (intptr_t cid = (kIllegalCid + 1); cid < kNumPredefinedCids; cid++) {
     if (isolate->class_table()->HasValidClassAt(cid)) {
       cls ^= isolate->class_table()->At(cid);
       ASSERT(builtin_vtables_[cid] == cls.raw_ptr()->handle_vtable_);
     }
   }
+  ASSERT(builtin_vtables_[kFreeListElement] == 0);
 #endif
 }
 
 
 void Object::RegisterClass(const Class& cls,
                            const String& name,
                            const Library& lib) {
   ASSERT(name.Length() > 0);
   ASSERT(name.CharAt(0) != '_');
   cls.set_name(name);
@@ skipping 17076 matching lines @@
   return "_MirrorReference";
 }
 
 
 void MirrorReference::PrintToJSONStream(JSONStream* stream, bool ref) const {
   Instance::PrintToJSONStream(stream, ref);
 }
 
 
 }  // namespace dart