Re-land: cc: Use worker context for one-copy tile initialization.

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 95e24788e8d97b05fdb04df26b3547177a4d9233..403267593193a25c6862dc62863b1c8984eb6f93 100644
--- a/cc/test/layer_tree_test.cc
+++ b/cc/test/layer_tree_test.cc
@@ -51,10 +51,9 @@ DrawResult TestHooks::PrepareToDrawOnThread(
 void TestHooks::CreateResourceAndTileTaskWorkerPool(
     LayerTreeHostImpl* host_impl,
     scoped_ptr<TileTaskWorkerPool>* tile_task_worker_pool,
-    scoped_ptr<ResourcePool>* resource_pool,
-    scoped_ptr<ResourcePool>* staging_resource_pool) {
+    scoped_ptr<ResourcePool>* resource_pool) {
   host_impl->LayerTreeHostImpl::CreateResourceAndTileTaskWorkerPool(
-      tile_task_worker_pool, resource_pool, staging_resource_pool);
+      tile_task_worker_pool, resource_pool);
 }
 
 // Adapts ThreadProxy for test. Injects test hooks for testing.
@@ -247,10 +246,9 @@ class LayerTreeHostImplForTesting : public LayerTreeHostImpl {
 
   void CreateResourceAndTileTaskWorkerPool(
       scoped_ptr<TileTaskWorkerPool>* tile_task_worker_pool,
-      scoped_ptr<ResourcePool>* resource_pool,
-      scoped_ptr<ResourcePool>* staging_resource_pool) override {
+      scoped_ptr<ResourcePool>* resource_pool) override {
     test_hooks_->CreateResourceAndTileTaskWorkerPool(
-        this, tile_task_worker_pool, resource_pool, staging_resource_pool);
+        this, tile_task_worker_pool, resource_pool);
   }
 
   void WillBeginImplFrame(const BeginFrameArgs& args) override {