Allow task pools to reason about transparency.

cc/raster/gpu_tile_task_worker_pool.h

 // Copyright 2014 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_RASTER_GPU_TILE_TASK_WORKER_POOL_H_
 #define CC_RASTER_GPU_TILE_TASK_WORKER_POOL_H_
 
 #include "base/memory/weak_ptr.h"
 #include "cc/raster/tile_task_runner.h"
 #include "cc/raster/tile_task_worker_pool.h"
@@ skipping 18 matching lines @@
       int gpu_rasterization_msaa_sample_count);
 
   // Overridden from TileTaskWorkerPool:
   TileTaskRunner* AsTileTaskRunner() override;
 
   // Overridden from TileTaskRunner:
   void SetClient(TileTaskRunnerClient* client) override;
   void Shutdown() override;
   void ScheduleTasks(TileTaskQueue* queue) override;
   void CheckForCompletedTasks() override;
-  ResourceFormat GetResourceFormat() const override;
-  bool GetResourceRequiresSwizzle() const override;
+  ResourceFormat GetResourceFormat(bool must_support_alpha) const override;
+  bool GetResourceRequiresSwizzle(bool must_support_alpha) const override;
 
   // Overridden from TileTaskClient:
   scoped_ptr<RasterBuffer> AcquireBufferForRaster(
       const Resource* resource,
       uint64_t resource_content_id,
       uint64_t previous_content_id) override;
   void ReleaseBufferForRaster(scoped_ptr<RasterBuffer> buffer) override;
 
  private:
   GpuTileTaskWorkerPool(base::SequencedTaskRunner* task_runner,
@@ skipping 25 matching lines @@
       task_set_finished_weak_ptr_factory_;
 
   base::WeakPtrFactory<GpuTileTaskWorkerPool> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(GpuTileTaskWorkerPool);
 };
 
 }  // namespace cc
 
 #endif  // CC_RASTER_GPU_TILE_TASK_WORKER_POOL_H_