cc: Make image controller return a status with the callback.

cc/tiles/image_controller.h

 // Copyright 2016 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 CC_TILES_IMAGE_CONTROLLER_H_
 #define CC_TILES_IMAGE_CONTROLLER_H_
 
 #include <set>
 #include <vector>
 
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/weak_ptr.h"
 #include "base/threading/simple_thread.h"
 #include "cc/base/cc_export.h"
 #include "cc/base/unique_notifier.h"
 #include "cc/playback/draw_image.h"
 #include "cc/raster/tile_task.h"
 #include "cc/tiles/image_decode_cache.h"
 
 namespace cc {
 
 class CC_EXPORT ImageController {
  public:
+  enum class ImageDecodeResult { SUCCESS, DECODE_NOT_REQUIRED, FAILURE };
+
   using ImageDecodeRequestId = uint64_t;
-  using ImageDecodedCallback = base::Callback<void(ImageDecodeRequestId)>;
+  using ImageDecodedCallback =
+      base::Callback<void(ImageDecodeRequestId, ImageDecodeResult)>;
   explicit ImageController(
       base::SequencedTaskRunner* origin_task_runner,
       scoped_refptr<base::SequencedTaskRunner> worker_task_runner);
   virtual ~ImageController();
 
   void SetImageDecodeCache(ImageDecodeCache* cache);
   void GetTasksForImagesAndRef(
       std::vector<DrawImage>* images,
       std::vector<scoped_refptr<TileTask>>* tasks,
       const ImageDecodeCache::TracingInfo& tracing_info);
@@ skipping 64 matching lines @@
   bool abort_tasks_ = false;
 
   base::WeakPtrFactory<ImageController> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(ImageController);
 };
 
 }  // namespace cc
 
 #endif  // CC_TILES_IMAGE_CONTROLLER_H_