Adds a gfx_export.h to ui/gfx and converts all code in ui/gfx to

ui/gfx/image/image_skia_rep.h

 // 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.
 
 #ifndef UI_GFX_IMAGE_IMAGE_SKIA_REP_H_
 #define UI_GFX_IMAGE_IMAGE_SKIA_REP_H_
 
 #include "third_party/skia/include/core/SkBitmap.h"
 #include "ui/base/layout.h"
-#include "ui/base/ui_export.h"
+#include "ui/gfx/gfx_export.h"
 #include "ui/gfx/size.h"
 
 namespace gfx {
 
 // An ImageSkiaRep represents a bitmap and the scale factor it is intended for.
 class UI_EXPORT ImageSkiaRep {
  public:
   // Create null bitmap.
   ImageSkiaRep();
   ~ImageSkiaRep();
@@ skipping 31 matching lines @@
   friend class ImageSkia;
   SkBitmap& mutable_sk_bitmap() { return bitmap_; }
 
   SkBitmap bitmap_;
   ui::ScaleFactor scale_factor_;
 };
 
 }  // namespace gfx
 
 #endif  // UI_GFX_IMAGE_IMAGE_SKIA_REP_H_