cc: Use CheckedNumeric for resource size calculations.

cc/resources/resource.cc

 // Copyright 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "cc/resources/resource.h"
 
 namespace cc {
 
 size_t Resource::bytes() const {
   if (size_.IsEmpty())
     return 0;
 
-  return MemorySizeBytes(size_, format_);
+  return UncheckedMemorySizeBytes(size_, format_);
 }
 
 
 }  // namespace cc