cc: Add mailbox support to ResourceProvider write locks.

cc/trees/layer_tree_host_impl.cc

Index: cc/trees/layer_tree_host_impl.cc
diff --git a/cc/trees/layer_tree_host_impl.cc b/cc/trees/layer_tree_host_impl.cc
index 89e1ebb179cce05fffe452724bca7143f55ae8a7..17e3af36895904cb42a6e174297a92a214a54c9d 100644
--- a/cc/trees/layer_tree_host_impl.cc
+++ b/cc/trees/layer_tree_host_impl.cc
@@ -2203,7 +2203,8 @@ void LayerTreeHostImpl::CreateResourceAndRasterBufferProvider(
 
     *raster_buffer_provider = GpuRasterBufferProvider::Create(
         context_provider, resource_provider_.get(),
-        settings_.use_distance_field_text, msaa_sample_count);
+        settings_.use_distance_field_text, msaa_sample_count,
+        settings_.async_worker_context_enabled);
     return;
   }
 
@@ -2238,7 +2239,8 @@ void LayerTreeHostImpl::CreateResourceAndRasterBufferProvider(
       GetTaskRunner(), context_provider, resource_provider_.get(),
       max_copy_texture_chromium_size, settings_.use_partial_raster,
       settings_.max_staging_buffer_usage_in_bytes,
-      settings_.renderer_settings.preferred_tile_format);
+      settings_.renderer_settings.preferred_tile_format,
+      settings_.async_worker_context_enabled);
 }
 
 void LayerTreeHostImpl::SetLayerTreeMutator(LayerTreeMutator* mutator) {