cc: Parameterize the main thread task runner

android_webview/browser/hardware_renderer.cc

 // 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.
 
 #include "android_webview/browser/hardware_renderer.h"
 
 #include "android_webview/browser/aw_gl_surface.h"
 #include "android_webview/browser/deferred_gpu_command_service.h"
 #include "android_webview/browser/parent_output_surface.h"
 #include "android_webview/browser/shared_renderer_state.h"
@@ skipping 73 matching lines @@
 
   cc::LayerTreeSettings settings;
 
   // Should be kept in sync with compositor_impl_android.cc.
   settings.allow_antialiasing = false;
   settings.highp_threshold_min = 2048;
 
   // Webview does not own the surface so should not clear it.
   settings.should_clear_root_render_pass = false;
 
-  layer_tree_host_ =
-      cc::LayerTreeHost::CreateSingleThreaded(this, this, NULL, settings);
+  layer_tree_host_ = cc::LayerTreeHost::CreateSingleThreaded(
+      this, this, NULL, settings, base::MessageLoopProxy::current());

[boliu, 2014/07/17 18:58:29]

I think this can just be null

[Sami, 2014/07/18 10:54:11]

Done.

   layer_tree_host_->SetRootLayer(root_layer_);
   layer_tree_host_->SetLayerTreeHostClientReady();
   layer_tree_host_->set_has_transparent_background(true);
 }
 
 HardwareRenderer::~HardwareRenderer() {
   // Must reset everything before |resource_collection_| to ensure all
   // resources are returned before resetting |resource_collection_| client.
   layer_tree_host_.reset();
   root_layer_ = NULL;
@@ skipping 118 matching lines @@
 }
 
 void HardwareRenderer::UnusedResourcesAreAvailable() {
   cc::ReturnedResourceArray returned_resources;
   resource_collection_->TakeUnusedResourcesForChildCompositor(
       &returned_resources);
   shared_renderer_state_->InsertReturnedResources(returned_resources);
 }
 
 }  // namespace android_webview