cc: GPU rasterize tiles synchronously in PrepareToDraw.

cc/test/layer_tree_test.cc

Index: cc/test/layer_tree_test.cc
diff --git a/cc/test/layer_tree_test.cc b/cc/test/layer_tree_test.cc
index f3f20238553d4fb5a703a2312f885058a6c8114f..a2154c2884572ebb6038400caf0df9d5f992c08a 100644
--- a/cc/test/layer_tree_test.cc
+++ b/cc/test/layer_tree_test.cc
@@ -46,6 +46,11 @@ DrawResult TestHooks::PrepareToDrawOnThread(
   return draw_result;
 }
 
+void TestHooks::CreateRasterizer(LayerTreeHostImpl* host_impl,
+                                 scoped_ptr<Rasterizer>* rasterizer) {
+  host_impl->LayerTreeHostImpl::CreateRasterizer(rasterizer);
+}
+
 void TestHooks::CreateResourceAndTileTaskWorkerPool(
     LayerTreeHostImpl* host_impl,
     scoped_ptr<TileTaskWorkerPool>* tile_task_worker_pool,
@@ -166,6 +171,10 @@ class LayerTreeHostImplForTesting : public LayerTreeHostImpl {
         block_notify_ready_to_activate_for_testing_(false),
         notify_ready_to_activate_was_blocked_(false) {}
 
+  void CreateRasterizer(scoped_ptr<Rasterizer>* rasterizer) override {
+    test_hooks_->CreateRasterizer(this, rasterizer);
+  }
+
   void CreateResourceAndTileTaskWorkerPool(
       scoped_ptr<TileTaskWorkerPool>* tile_task_worker_pool,
       scoped_ptr<ResourcePool>* resource_pool,