Revert of cc: Add image decode queue functionality to image manager.

cc/tiles/software_image_decode_cache.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_SOFTWARE_IMAGE_DECODE_CACHE_H_
 #define CC_TILES_SOFTWARE_IMAGE_DECODE_CACHE_H_
 
 #include <stdint.h>
 
 #include <memory>
@@ skipping 91 matching lines @@
 };
 
 class CC_EXPORT SoftwareImageDecodeCache
     : public ImageDecodeCache,
       public base::trace_event::MemoryDumpProvider,
       public base::MemoryCoordinatorClient {
  public:
   using ImageKey = ImageDecodeCacheKey;
   using ImageKeyHash = ImageDecodeCacheKeyHash;
 
-  enum class DecodeTaskType { USE_IN_RASTER_TASKS, USE_OUT_OF_RASTER_TASKS };
-
   SoftwareImageDecodeCache(ResourceFormat format,
                            size_t locked_memory_limit_bytes);
   ~SoftwareImageDecodeCache() override;
 
   // ImageDecodeCache overrides.
   bool GetTaskForImageAndRef(const DrawImage& image,
                              const TracingInfo& tracing_info,
                              scoped_refptr<TileTask>* task) override;
-  bool GetOutOfRasterDecodeTaskForImageAndRef(
-      const DrawImage& image,
-      scoped_refptr<TileTask>* task) override;
   void UnrefImage(const DrawImage& image) override;
   DecodedDrawImage GetDecodedImageForDraw(const DrawImage& image) override;
   void DrawWithImageFinished(const DrawImage& image,
                              const DecodedDrawImage& decoded_image) override;
   void ReduceCacheUsage() override;
   // Software doesn't keep outstanding images pinned, so this is a no-op.
   void SetShouldAggressivelyFreeResources(
       bool aggressively_free_resources) override {}
 
   // Decode the given image and store it in the cache. This is only called by an
   // image decode task from a worker thread.
-  void DecodeImage(const ImageKey& key,
-                   const DrawImage& image,
-                   DecodeTaskType task_type);
+  void DecodeImage(const ImageKey& key, const DrawImage& image);
 
-  void RemovePendingTask(const ImageKey& key, DecodeTaskType task_type);
+  void RemovePendingTask(const ImageKey& key);
 
   // MemoryDumpProvider overrides.
   bool OnMemoryDump(const base::trace_event::MemoryDumpArgs& args,
                     base::trace_event::ProcessMemoryDump* pmd) override;
 
  private:
   // DecodedImage is a convenience storage for discardable memory. It can also
   // construct an image out of SkImageInfo and stored discardable memory.
   class DecodedImage {
    public:
@@ skipping 116 matching lines @@
   void UnrefAtRasterImage(const ImageKey& key);
 
   // Helper function which dumps all images in a specific ImageMRUCache.
   void DumpImageMemoryForCache(const ImageMRUCache& cache,
                                const char* cache_name,
                                base::trace_event::ProcessMemoryDump* pmd) const;
 
   // Overriden from base::MemoryCoordinatorClient.
   void OnMemoryStateChange(base::MemoryState state) override;
 
-  // Helper method to get the different tasks. Note that this should be used as
-  // if it was public (ie, all of the locks need to be properly acquired).
-  bool GetTaskForImageAndRefInternal(const DrawImage& image,
-                                     const TracingInfo& tracing_info,
-                                     DecodeTaskType type,
-                                     scoped_refptr<TileTask>* task);
-
   std::unordered_map<ImageKey, scoped_refptr<TileTask>, ImageKeyHash>
-      pending_in_raster_image_tasks_;
-  std::unordered_map<ImageKey, scoped_refptr<TileTask>, ImageKeyHash>
-      pending_out_of_raster_image_tasks_;
+      pending_image_tasks_;
 
   // The members below this comment can only be accessed if the lock is held to
   // ensure that they are safe to access on multiple threads.
   base::Lock lock_;
 
   // Decoded images and ref counts (predecode path).
   ImageMRUCache decoded_images_;
   std::unordered_map<ImageKey, int, ImageKeyHash> decoded_images_ref_counts_;
 
   // Decoded image and ref counts (at-raster decode path).
   ImageMRUCache at_raster_decoded_images_;
   std::unordered_map<ImageKey, int, ImageKeyHash>
       at_raster_decoded_images_ref_counts_;
 
   MemoryBudget locked_images_budget_;
 
   ResourceFormat format_;
   size_t max_items_in_cache_;
 
   // Used to uniquely identify DecodedImages for memory traces.
   base::AtomicSequenceNumber next_tracing_id_;
 };
 
 }  // namespace cc
 
 #endif  // CC_TILES_SOFTWARE_IMAGE_DECODE_CACHE_H_