cc: Unittest for checking already failed image decode task.

cc/tiles/gpu_image_decode_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_GPU_IMAGE_DECODE_CONTROLLER_H_
 #define CC_TILES_GPU_IMAGE_DECODE_CONTROLLER_H_
 
 #include <memory>
 #include <unordered_map>
 #include <vector>
@@ skipping 72 matching lines @@
   void UploadTaskCompleted(const DrawImage& image);
 
   // For testing only.
   void SetCachedItemLimitForTesting(size_t limit) {
     cached_items_limit_ = limit;
   }
   void SetCachedBytesLimitForTesting(size_t limit) {
     cached_bytes_limit_ = limit;
   }
   size_t GetBytesUsedForTesting() const { return bytes_used_; }
+  void SetImageDecodingFailedForTesting(const DrawImage& image);
 
  private:
   enum class DecodedDataMode { GPU, CPU };
 
   // Stores the CPU-side decoded bits of an image and supporting fields.
   struct DecodedImageData {
     DecodedImageData();
     ~DecodedImageData();
 
     // May be null if image not yet decoded.
@@ skipping 86 matching lines @@
 
   // We can't release GPU backed SkImages without holding the context lock,
   // so we add them to this list and defer deletion until the next time the lock
   // is held.
   std::vector<sk_sp<SkImage>> images_pending_deletion_;
 };
 
 }  // namespace cc
 
 #endif  // CC_TILES_GPU_IMAGE_DECODE_CONTROLLER_H_