ui/gfx: Remove the deprecated "operator const GdkPixbuf*" from Image API.

ui/base/resource/resource_bundle_gtk.cc

 // Copyright (c) 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 "ui/base/resource/resource_bundle.h"
 
 #include "base/i18n/rtl.h"
 #include "base/logging.h"
 #include "base/synchronization/lock.h"
 #include "third_party/skia/include/core/SkBitmap.h"
@@ skipping 73 matching lines @@
     images_[key] = image;
     return image;
   }
 
   LOG(WARNING) << "Unable to pixbuf with id " << resource_id;
   NOTREACHED();  // Want to assert in debug mode.
   return GetEmptyImage();
 }
 
 GdkPixbuf* ResourceBundle::GetRTLEnabledPixbufNamed(int resource_id) {
-  return *GetPixbufImpl(resource_id, true);
+  return GetPixbufImpl(resource_id, true)->ToGdkPixbuf();
 }
 
 gfx::Image& ResourceBundle::GetRTLEnabledImageNamed(int resource_id) {
   return *GetPixbufImpl(resource_id, true);
 }
 
 }  // namespace ui