cc: Implement states for Task for stricter control.

content/renderer/raster_worker_pool.cc

 // Copyright 2015 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 "content/renderer/raster_worker_pool.h"
 
 #include <string>
 #include <utility>
 #include <vector>
 
@@ skipping 334 matching lines @@
   TRACE_EVENT0("toplevel", "TaskGraphRunner::RunTask");
 
   lock_.AssertAcquired();
 
   auto prioritized_task = work_queue_.GetNextTaskToRun(category);
   cc::Task* task = prioritized_task.task;
 
   // There may be more work available, so wake up another worker thread.
   SignalHasReadyToRunTasksWithLockAcquired();
 
-  // Call WillRun() before releasing |lock_| and running task.
-  task->WillRun();
-
   {
     base::AutoUnlock unlock(lock_);
 
     task->RunOnWorkerThread();
   }
 
-  // This will mark task as finished running.
-  task->DidRun();
-
   work_queue_.CompleteTask(prioritized_task);
 
   // If namespace has finished running all tasks, wake up origin threads.
   if (work_queue_.HasFinishedRunningTasksInNamespace(
           prioritized_task.task_namespace))
     has_namespaces_with_finished_running_tasks_cv_.Signal();
 }
 
 bool RasterWorkerPool::ShouldRunTaskForCategoryWithLockAcquired(
     cc::TaskCategory category) {
@@ skipping 47 matching lines @@
 
 // Overridden from cc::Task:
 void RasterWorkerPool::ClosureTask::RunOnWorkerThread() {
   closure_.Run();
   closure_.Reset();
 }
 
 RasterWorkerPool::ClosureTask::~ClosureTask() {}
 
 }  // namespace content