cc: Simplify Task and its derived classes.

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 43 matching lines @@
   explicit GpuImageDecodeController(ContextProvider* context,
                                     ResourceFormat decode_format);
   ~GpuImageDecodeController() override;
 
   // ImageDecodeController overrides.
 
   // Finds the existing uploaded image for the provided DrawImage. Creates an
   // upload task to upload the image if an exsiting image does not exist.
   bool GetTaskForImageAndRef(const DrawImage& image,
                              uint64_t prepare_tiles_id,
-                             scoped_refptr<ImageDecodeTask>* task) override;
+                             scoped_refptr<TileTask>* task) override;
   void UnrefImage(const DrawImage& image) override;
   DecodedDrawImage GetDecodedImageForDraw(const DrawImage& draw_image) override;
   void DrawWithImageFinished(const DrawImage& image,
                              const DecodedDrawImage& decoded_image) override;
   void ReduceCacheUsage() override;
   void SetShouldAggressivelyFreeResources(
       bool aggressively_free_resources) override;
 
   // Called by Decode / Upload tasks.
   void DecodeImage(const DrawImage& image);
@@ skipping 53 matching lines @@
 
   using ImageDataMRUCache =
       base::MRUCache<uint32_t, std::unique_ptr<ImageData>>;
 
   // All private functions should only be called while holding |lock_|. Some
   // functions also require the |context_| lock. These are indicated by
   // additional comments.
 
   // Similar to GetTaskForImageAndRef, but gets the dependent decode task
   // rather than the upload task, if necessary.
-  scoped_refptr<ImageDecodeTask> GetImageDecodeTaskAndRef(
-      const DrawImage& image,
-      uint64_t prepare_tiles_id);
+  scoped_refptr<TileTask> GetImageDecodeTaskAndRef(const DrawImage& image,
+                                                   uint64_t prepare_tiles_id);
 
   void RefImageDecode(const DrawImage& draw_image);
   void UnrefImageDecode(const DrawImage& draw_image);
   void RefImage(const DrawImage& draw_image);
   void UnrefImageInternal(const DrawImage& draw_image);
   void RefCountChanged(ImageData* image_data);
 
   // Ensures that the cache can hold an element of |required_size|, freeing
   // unreferenced cache entries if necessary to make room.
   bool EnsureCapacity(size_t required_size);
@@ skipping 12 matching lines @@
                               ImageData* image_data);
   void DeletePendingImages();
 
   const ResourceFormat format_;
   ContextProvider* context_;
   skia::RefPtr<GrContextThreadSafeProxy> context_threadsafe_proxy_;
 
   // All members below this point must only be accessed while holding |lock_|.
   base::Lock lock_;
 
-  std::unordered_map<uint32_t, scoped_refptr<ImageDecodeTask>>
+  std::unordered_map<uint32_t, scoped_refptr<TileTask>>
       pending_image_upload_tasks_;
-  std::unordered_map<uint32_t, scoped_refptr<ImageDecodeTask>>
+  std::unordered_map<uint32_t, scoped_refptr<TileTask>>
       pending_image_decode_tasks_;
 
   ImageDataMRUCache image_data_;
 
   size_t cached_items_limit_;
   size_t cached_bytes_limit_;
   size_t bytes_used_;
 
   // 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<skia::RefPtr<SkImage>> images_pending_deletion_;
 };
 
 }  // namespace cc
 
 #endif  // CC_TILES_GPU_IMAGE_DECODE_CONTROLLER_H_