Fix for potential memory leak after putting to WeakObjectToCodeDependency table.

R=ulan@chromium.org

Review URL: https://codereview.chromium.org/254723004

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@20973 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/heap.cc

@@ -5656,6 +5656,7 @@ void Heap::AddWeakObjectToCodeDependency(Handle<Object> obj,
                                          Handle<DependentCode> dep) {
   ASSERT(!InNewSpace(*obj));
   ASSERT(!InNewSpace(*dep));
+  HandleScope scope(isolate());
   Handle<WeakHashTable> table(WeakHashTable::cast(weak_object_to_code_table_),
                               isolate());
   table = WeakHashTable::Put(table, obj, dep);