cc: Rename ImageDecodeController to ImageDecodeCache.

cc/tiles/image_decode_cache.h

 // Copyright 2015 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_DECODE_CONTROLLER_H_
-#define CC_TILES_IMAGE_DECODE_CONTROLLER_H_
+#ifndef CC_TILES_IMAGE_DECODE_CACHE_H_
+#define CC_TILES_IMAGE_DECODE_CACHE_H_
 
 #include "base/memory/ref_counted.h"
 #include "cc/playback/decoded_draw_image.h"
 #include "cc/playback/draw_image.h"
 #include "cc/tiles/tile_priority.h"
 
 namespace cc {
 
 class TileTask;
 
-// ImageDecodeController is responsible for generating decode tasks, decoding
+// ImageDecodeCache is responsible for generating decode tasks, decoding
 // images, storing images in cache, and being able to return the decoded images
 // when requested.
 
-// ImageDecodeController is responsible for the following things:
+// ImageDecodeCache is responsible for the following things:
 // 1. Given a DrawImage, it can return an TileTask which when run will
 //    decode and cache the resulting image. If the image does not need a task to
 //    be decoded, then nullptr will be returned. The return value of the
 //    function indicates whether the image was or is going to be locked, so an
 //    unlock will be required.
 // 2. Given a cache key and a DrawImage, it can decode the image and store it in
 //    the cache. Note that it is important that this function is only accessed
 //    via an image decode task.
 // 3. Given a DrawImage, it can return a DecodedDrawImage, which represented the
 //    decoded version of the image. Note that if the image is not in the cache
 //    and it needs to be scaled/decoded, then this decode will happen as part of
 //    getting the image. As such, this should only be accessed from a raster
 //    thread.
-class CC_EXPORT ImageDecodeController {
+class CC_EXPORT ImageDecodeCache {
  public:
   // This information should be used strictly in tracing, UMA, and any other
   // reporting systems.
   struct TracingInfo {
     TracingInfo(uint64_t prepare_tiles_id,
                 TilePriority::PriorityBin requesting_tile_bin)
         : prepare_tiles_id(prepare_tiles_id),
           requesting_tile_bin(requesting_tile_bin) {}
     TracingInfo() : TracingInfo(0, TilePriority::NOW) {}
 
     // ID for the current prepare tiles call.
     const uint64_t prepare_tiles_id;
 
     // The bin of the tile that caused this image to be requested.
     const TilePriority::PriorityBin requesting_tile_bin;
   };
 
-  virtual ~ImageDecodeController() {}
+  virtual ~ImageDecodeCache() {}
 
   // Fill in an TileTask which will decode the given image when run. In
   // case the image is already cached, fills in nullptr. Returns true if the
   // image needs to be unreffed when the caller is finished with it.
   //
   // This is called by the tile manager (on the compositor thread) when creating
   // a raster task.
   virtual bool GetTaskForImageAndRef(const DrawImage& image,
                                      const TracingInfo& tracing_info,
                                      scoped_refptr<TileTask>* task) = 0;
   // Unrefs an image. When the tile is finished, this should be called for every
   // GetTaskForImageAndRef call that returned true.
   virtual void UnrefImage(const DrawImage& image) = 0;
 
   // Returns a decoded draw image. This may cause a decode if the image was not
   // predecoded.
   //
   // This is called by a raster task (on a worker thread) when an image is
   // required.
   virtual DecodedDrawImage GetDecodedImageForDraw(const DrawImage& image) = 0;
   // Unrefs an image. This should be called for every GetDecodedImageForDraw
   // when the draw with the image is finished.
   virtual void DrawWithImageFinished(const DrawImage& image,
                                      const DecodedDrawImage& decoded_image) = 0;
 
-  // This function informs the controller that now is a good time to clean up
+  // This function informs the cache that now is a good time to clean up
   // memory. This is called periodically from the compositor thread.
   virtual void ReduceCacheUsage() = 0;
 
-  // This function informs the controller that we are hidden and should not be
+  // This function informs the cache that we are hidden and should not be
   // retaining cached resources longer than needed.
   virtual void SetShouldAggressivelyFreeResources(
       bool aggressively_free_resources) = 0;
 };
 
 }  // namespace cc
 
-#endif  // CC_TILES_IMAGE_DECODE_CONTROLLER_H_
+#endif  // CC_TILES_IMAGE_DECODE_CACHE_H_