Revert of cc: Single-threaded impl-side painting for unit tests

cc/trees/layer_tree_host_impl.cc

 // Copyright 2011 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/trees/layer_tree_host_impl.h"
 
 #include <algorithm>
 #include <limits>
 
 #include "base/basictypes.h"
@@ skipping 1925 matching lines @@
   if (pending_tree_)
     pending_tree_->set_needs_update_draw_properties();
   client_->UpdateRendererCapabilitiesOnImplThread();
 }
 
 void LayerTreeHostImpl::CreateAndSetTileManager() {
   DCHECK(!tile_manager_);
   DCHECK(settings_.impl_side_painting);
   DCHECK(output_surface_);
   DCHECK(resource_provider_);
-  base::SingleThreadTaskRunner* task_runner =
-      proxy_->HasImplThread() ? proxy_->ImplThreadTaskRunner()
-                              : proxy_->MainThreadTaskRunner();
-  DCHECK(task_runner);
+  DCHECK(proxy_->ImplThreadTaskRunner());
 
   ContextProvider* context_provider = output_surface_->context_provider();
   transfer_buffer_memory_limit_ =
       GetMaxTransferBufferUsageBytes(context_provider, settings_.refresh_rate);
 
   if (use_gpu_rasterization_ && context_provider) {
     resource_pool_ =
         ResourcePool::Create(resource_provider_.get(),
                              GL_TEXTURE_2D,
                              resource_provider_->best_texture_format());
 
-    raster_worker_pool_ = GpuRasterWorkerPool::Create(
-        task_runner, context_provider, resource_provider_.get());
+    raster_worker_pool_ =
+        GpuRasterWorkerPool::Create(proxy_->ImplThreadTaskRunner(),
+                                    context_provider,
+                                    resource_provider_.get());
   } else if (UseOneCopyTextureUpload() && context_provider) {
     // We need to create a staging resource pool when using copy rasterizer.
     staging_resource_pool_ =
         ResourcePool::Create(resource_provider_.get(),
                              GetMapImageTextureTarget(context_provider),
                              resource_provider_->best_texture_format());
     resource_pool_ =
         ResourcePool::Create(resource_provider_.get(),
                              GL_TEXTURE_2D,
                              resource_provider_->best_texture_format());
 
     raster_worker_pool_ = ImageCopyRasterWorkerPool::Create(
-        task_runner,
+        proxy_->ImplThreadTaskRunner(),
         RasterWorkerPool::GetTaskGraphRunner(),
         context_provider,
         resource_provider_.get(),
         staging_resource_pool_.get());
   } else if (!UseZeroCopyTextureUpload() && context_provider) {
     resource_pool_ = ResourcePool::Create(
         resource_provider_.get(),
         GL_TEXTURE_2D,
         resource_provider_->memory_efficient_texture_format());
 
     raster_worker_pool_ = PixelBufferRasterWorkerPool::Create(
-        task_runner,
+        proxy_->ImplThreadTaskRunner(),
         RasterWorkerPool::GetTaskGraphRunner(),
         context_provider,
         resource_provider_.get(),
         transfer_buffer_memory_limit_);
   } else {
     resource_pool_ =
         ResourcePool::Create(resource_provider_.get(),
                              GetMapImageTextureTarget(context_provider),
                              resource_provider_->best_texture_format());
 
     raster_worker_pool_ =
-        ImageRasterWorkerPool::Create(task_runner,
+        ImageRasterWorkerPool::Create(proxy_->ImplThreadTaskRunner(),
                                       RasterWorkerPool::GetTaskGraphRunner(),
                                       resource_provider_.get());
   }
 
-  tile_manager_ = TileManager::Create(this,
-                                      task_runner,
-                                      resource_pool_.get(),
-                                      raster_worker_pool_->AsRasterizer(),
-                                      rendering_stats_instrumentation_);
+  tile_manager_ =
+      TileManager::Create(this,
+                          proxy_->ImplThreadTaskRunner(),
+                          resource_pool_.get(),
+                          raster_worker_pool_->AsRasterizer(),
+                          rendering_stats_instrumentation_);
 
   UpdateTileManagerMemoryPolicy(ActualManagedMemoryPolicy());
   need_to_update_visible_tiles_before_draw_ = false;
 }
 
 void LayerTreeHostImpl::DestroyTileManager() {
   tile_manager_.reset();
   resource_pool_.reset();
   staging_resource_pool_.reset();
   raster_worker_pool_.reset();
@@ skipping 1339 matching lines @@
 }
 
 void LayerTreeHostImpl::UnregisterPictureLayerImpl(PictureLayerImpl* layer) {
   std::vector<PictureLayerImpl*>::iterator it =
       std::find(picture_layers_.begin(), picture_layers_.end(), layer);
   DCHECK(it != picture_layers_.end());
   picture_layers_.erase(it);
 }
 
 }  // namespace cc