Check that AllocationMementos never get scavengend.

BUG=
R=mstarzinger@chromium.org, mvstanton@chromium.org

Review URL: https://codereview.chromium.org/24052003

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@16628 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/heap-inl.h

@@ -525,6 +525,8 @@ void Heap::ScavengeObject(HeapObject** p, HeapObject* object) {
     return;
   }
 
+  // TODO(hpayer): temporary debugging code for issue 284577.
+  CHECK(object->map() != object->GetHeap()->allocation_memento_map());
   // Call the slow part of scavenge object.
   return ScavengeObjectSlow(p, object);
 }