services/ui: Revert CLs that broke Windows.

services/ui/gles2/command_buffer_task_runner.h

+// Copyright 2014 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.
+
+#ifndef SERVICES_UI_GLES2_COMMAND_BUFFER_TASK_RUNNER_H_
+#define SERVICES_UI_GLES2_COMMAND_BUFFER_TASK_RUNNER_H_
+
+#include <deque>
+#include <map>
+#include <memory>
+
+#include "base/callback.h"
+#include "base/macros.h"
+#include "base/memory/ref_counted.h"
+#include "base/single_thread_task_runner.h"
+#include "base/synchronization/condition_variable.h"
+#include "base/synchronization/lock.h"
+#include "base/threading/thread_checker.h"
+
+namespace ui {
+
+class CommandBufferDriver;
+
+// This class maintains tasks submitted by |CommandBufferImpl|. Those tasks will
+// be executed on the main thread. But if the main thread is blocked in
+// |CommandBufferLocal::OnWaitFenceSync()| by waiting a sync point, the
+// |CommandBufferTaskRunner::RunOneTask()| could be used for executing a task
+// from other command buffers which may retire the sync point.
+class CommandBufferTaskRunner
+    : public base::RefCountedThreadSafe<CommandBufferTaskRunner> {
+ public:
+  CommandBufferTaskRunner();
+
+  // TaskCallback returns true if the task is completed and should be removed
+  // from the task queue, otherwise returns false.
+  typedef base::Callback<bool(void)> TaskCallback;
+  bool PostTask(const CommandBufferDriver* driver,
+                const TaskCallback& task);
+
+  scoped_refptr<base::SingleThreadTaskRunner> task_runner() const {
+    return task_runner_;
+  }
+
+ private:
+  friend class base::RefCountedThreadSafe<CommandBufferTaskRunner>;
+
+  ~CommandBufferTaskRunner();
+
+  // Run one command buffer task from a scheduled command buffer.
+  // When there isn't any command buffer task, and if the |block| is false,
+  // this function will return false immediately, otherwise, this function
+  // will be blocked until a task is available for executing.
+  bool RunOneTaskInternalLocked();
+
+  // Post a task to the main thread to execute tasks in |driver_map_|, if it is
+  // necessary.
+  void ScheduleTaskIfNecessaryLocked();
+
+  // The callback function for executing tasks in |driver_map_|.
+  void RunCommandBufferTask();
+
+  base::ThreadChecker thread_checker_;
+  scoped_refptr<base::SingleThreadTaskRunner> task_runner_;
+
+  typedef std::deque<TaskCallback> TaskQueue;
+  typedef std::map<const CommandBufferDriver*, TaskQueue> DriverMap;
+  DriverMap driver_map_;
+  bool need_post_task_;
+
+  // The access lock for |driver_map_| and |need_post_task_|.
+  base::Lock lock_;
+
+  DISALLOW_COPY_AND_ASSIGN(CommandBufferTaskRunner);
+};
+
+}  // namespace ui
+
+#endif  // SERVICES_UI_GLES2_COMMAND_BUFFER_TASK_RUNNER_H_