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

ui/gfx/image/image.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/gfx/image/image.h"
 
 #include <algorithm>
 
 #include "base/logging.h"
 #include "base/stl_util.h"
@@ skipping 312 matching lines @@
   NSImage* image = ToNSImage();
   base::mac::NSObjectRetain(image);
   return image;
 }
 #endif
 
 Image::operator const SkBitmap&() const {
   return *ToSkBitmap();
 }
 
-#if defined(TOOLKIT_USES_GTK)
-Image::operator GdkPixbuf*() const {
-  return ToGdkPixbuf();
-}
-#endif
-
 #if defined(OS_MACOSX)
 Image::operator NSImage*() const {
   return ToNSImage();
 }
 #endif
 
 bool Image::HasRepresentation(RepresentationType type) const {
   return storage_.get() && storage_->representations().count(type) != 0;
 }
 
@@ skipping 112 matching lines @@
   return GetRepresentation(Image::kImageRepSkia)->AsImageRepSkia()->
       bitmaps().size();
 }
 
 const SkBitmap* Image::GetSkBitmapAtIndex(size_t index) const {
   return GetRepresentation(Image::kImageRepSkia)->AsImageRepSkia()->
       bitmaps()[index];
 }
 
 }  // namespace gfx