cc: Remove ScheduleOnOriginThread() and CompleteOnOriginThread().

cc/tiles/gpu_image_decode_controller.cc

 // 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.
 
 #include "cc/tiles/gpu_image_decode_controller.h"
 
 #include "cc/debug/devtools_instrumentation.h"
 #include "cc/raster/tile_task_runner.h"
 #include "skia/ext/refptr.h"
 
@@ skipping 11 matching lines @@
 
   // Overridden from Task:
   void RunOnWorkerThread() override {
     TRACE_EVENT2("cc", "ImageDecodeTaskImpl::RunOnWorkerThread", "mode", "gpu",
                  "source_prepare_tiles_id", source_prepare_tiles_id_);
     devtools_instrumentation::ScopedImageDecodeTask image_decode_task(
         image_ref_.get());
     controller_->DecodeImage(image_);
   }
 
-  // Overridden from TileTask:
-  void ScheduleOnOriginThread(TileTaskClient* client) override {}
-  void CompleteOnOriginThread(TileTaskClient* client) override {
+ protected:
+  ~ImageDecodeTaskImpl() override {
     controller_->RemovePendingTaskForImage(image_);
   }
 
- protected:
-  ~ImageDecodeTaskImpl() override {}
-
  private:
   GpuImageDecodeController* controller_;
   DrawImage image_;
   skia::RefPtr<const SkImage> image_ref_;
   uint64_t source_prepare_tiles_id_;
 
   DISALLOW_COPY_AND_ASSIGN(ImageDecodeTaskImpl);
 };
 
 GpuImageDecodeController::GpuImageDecodeController() {}
@@ skipping 42 matching lines @@
   prerolled_images_.insert(image.image()->uniqueID());
 }
 
 void GpuImageDecodeController::RemovePendingTaskForImage(
     const DrawImage& image) {
   base::AutoLock lock(lock_);
   pending_image_tasks_.erase(image.image()->uniqueID());
 }
 
 }  // namespace cc