Reland of cc: Add mailbox support to ResourceProvider write locks.

cc/tiles/tile_task_manager.cc

 // Copyright 2016 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/tiles/tile_task_manager.h"
 
 #include "base/memory/ptr_util.h"
 #include "base/trace_event/trace_event.h"
 
 namespace cc {
 
 TileTaskManager::TileTaskManager() {}
 
 TileTaskManager::~TileTaskManager() {}
 
 // static
 std::unique_ptr<TileTaskManagerImpl> TileTaskManagerImpl::Create(
-    std::unique_ptr<RasterBufferProvider> raster_buffer_provider,
     TaskGraphRunner* task_graph_runner) {
-  return base::WrapUnique<TileTaskManagerImpl>(new TileTaskManagerImpl(
-      std::move(raster_buffer_provider), task_graph_runner));
+  return base::WrapUnique<TileTaskManagerImpl>(
+      new TileTaskManagerImpl(task_graph_runner));
 }
 
-TileTaskManagerImpl::TileTaskManagerImpl(
-    std::unique_ptr<RasterBufferProvider> raster_buffer_provider,
-    TaskGraphRunner* task_graph_runner)
-    : raster_buffer_provider_(std::move(raster_buffer_provider)),
-      task_graph_runner_(task_graph_runner),
+TileTaskManagerImpl::TileTaskManagerImpl(TaskGraphRunner* task_graph_runner)
+    : task_graph_runner_(task_graph_runner),
       namespace_token_(task_graph_runner->GetNamespaceToken()) {}
 
 TileTaskManagerImpl::~TileTaskManagerImpl() {}
 
 void TileTaskManagerImpl::ScheduleTasks(TaskGraph* graph) {
   TRACE_EVENT0("cc", "TileTaskManagerImpl::ScheduleTasks");
-
-  raster_buffer_provider_->OrderingBarrier();
   task_graph_runner_->ScheduleTasks(namespace_token_, graph);
 }
 
 void TileTaskManagerImpl::CheckForCompletedTasks() {
   TRACE_EVENT0("cc", "TileTaskManagerImpl::CheckForCompletedTasks");
   Task::Vector completed_tasks;
   task_graph_runner_->CollectCompletedTasks(namespace_token_, &completed_tasks);
 
   for (auto& task : completed_tasks) {
     DCHECK(task->state().IsFinished() || task->state().IsCanceled());
     TileTask* tile_task = static_cast<TileTask*>(task.get());
     tile_task->OnTaskCompleted();
     tile_task->DidComplete();
   }
 }
 
 void TileTaskManagerImpl::Shutdown() {
   TRACE_EVENT0("cc", "TileTaskManagerImpl::Shutdown");
 
   // Cancel non-scheduled tasks and wait for running tasks to finish.
   TaskGraph empty;
   task_graph_runner_->ScheduleTasks(namespace_token_, &empty);
   task_graph_runner_->WaitForTasksToFinishRunning(namespace_token_);
-
-  raster_buffer_provider_->Shutdown();
-}
-
-RasterBufferProvider* TileTaskManagerImpl::GetRasterBufferProvider() const {
-  return raster_buffer_provider_.get();
 }
 
 }  // namespace cc