(not for commit) Simplified multi-threaded Ganesh with lock on Flush only.

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 1942 matching lines @@
                           tile_task_worker_pool_->AsTileTaskRunner(),
                           rasterizer_.get(), scheduled_raster_task_limit);
 
   UpdateTileManagerMemoryPolicy(ActualManagedMemoryPolicy());
 }
 
 scoped_ptr<Rasterizer> LayerTreeHostImpl::CreateRasterizer() {
   ContextProvider* context_provider = output_surface_->context_provider();
   if (use_gpu_rasterization_ && context_provider) {
     return GpuRasterizer::Create(context_provider, resource_provider_.get(),
-                                 settings_.use_distance_field_text, false,
+                                 settings_.use_distance_field_text,
+                                 settings_.threaded_gpu_rasterization_enabled,
                                  settings_.gpu_rasterization_msaa_sample_count);
   }
   return SoftwareRasterizer::Create();
 }
 
 void LayerTreeHostImpl::CreateResourceAndTileTaskWorkerPool(
     scoped_ptr<TileTaskWorkerPool>* tile_task_worker_pool,
     scoped_ptr<ResourcePool>* resource_pool,
     scoped_ptr<ResourcePool>* staging_resource_pool) {
   base::SingleThreadTaskRunner* task_runner =
@@ skipping 114 matching lines @@
 
   if (!output_surface->BindToClient(this))
     return false;
 
   output_surface_ = output_surface.Pass();
   resource_provider_ = ResourceProvider::Create(
       output_surface_.get(), shared_bitmap_manager_, gpu_memory_buffer_manager_,
       proxy_->blocking_main_thread_task_runner(),
       settings_.renderer_settings.highp_threshold_min,
       settings_.renderer_settings.use_rgba_4444_textures,
+      use_gpu_rasterization() && settings_.threaded_gpu_rasterization_enabled,
       settings_.renderer_settings.texture_id_allocation_chunk_size);
 
   if (output_surface_->capabilities().deferred_gl_initialization)
     EnforceZeroBudget(true);
 
   CreateAndSetRenderer();
 
   if (settings_.impl_side_painting)
     CreateAndSetTileManager();
 
@@ skipping 1350 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