cc: Add image decode queue functionality to image manager.

content/renderer/gpu/render_widget_compositor.cc

 // Copyright (c) 2013 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 "content/renderer/gpu/render_widget_compositor.h"
 
 #include <stddef.h>
 
 #include <cmath>
 #include <limits>
 #include <string>
 #include <utility>
 
 #include "base/command_line.h"
 #include "base/location.h"
 #include "base/logging.h"
 #include "base/memory/ptr_util.h"
 #include "base/numerics/safe_conversions.h"
 #include "base/single_thread_task_runner.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/synchronization/lock.h"
 #include "base/sys_info.h"
+#include "base/task_scheduler/post_task.h"
+#include "base/task_scheduler/task_scheduler.h"
+#include "base/task_scheduler/task_traits.h"
 #include "base/threading/thread_task_runner_handle.h"
 #include "base/time/time.h"
 #include "base/values.h"
 #include "build/build_config.h"
 #include "cc/animation/animation_host.h"
 #include "cc/animation/animation_timeline.h"
 #include "cc/base/switches.h"
 #include "cc/blimp/engine_picture_cache.h"
 #include "cc/blimp/image_serialization_processor.h"
 #include "cc/blimp/layer_tree_host_remote.h"
@@ skipping 205 matching lines @@
     params.settings = &settings;
     layer_tree_host_ = base::MakeUnique<cc::LayerTreeHostRemote>(&params);
   } else {
     cc::LayerTreeHostInProcess::InitParams params;
     params.client = this;
     params.settings = &settings;
     params.task_graph_runner = compositor_deps_->GetTaskGraphRunner();
     params.main_task_runner =
         compositor_deps_->GetCompositorMainThreadTaskRunner();
     params.mutator_host = animation_host_.get();
+    if (base::TaskScheduler::GetInstance()) {
+      params.image_worker_task_runner =
+          base::CreateSequencedTaskRunnerWithTraits(
+              base::TaskTraits()
+                  .WithPriority(base::TaskPriority::BACKGROUND)
+                  .WithShutdownBehavior(
+                      base::TaskShutdownBehavior::CONTINUE_ON_SHUTDOWN));
+    }
     if (!threaded_) {
       // Single-threaded layout tests.
       layer_tree_host_ =
           cc::LayerTreeHostInProcess::CreateSingleThreaded(this, &params);
     } else {
       layer_tree_host_ = cc::LayerTreeHostInProcess::CreateThreaded(
           compositor_deps_->GetCompositorImplThreadTaskRunner(), &params);
     }
   }
 
@@ skipping 870 matching lines @@
     float device_scale) {
   layer_tree_host_->GetLayerTree()->SetPaintedDeviceScaleFactor(device_scale);
 }
 
 void RenderWidgetCompositor::SetDeviceColorSpace(
     const gfx::ColorSpace& color_space) {
   layer_tree_host_->GetLayerTree()->SetDeviceColorSpace(color_space);
 }
 
 }  // namespace content