[ash-md] Added a delay between system menu default/detailed view transitions.

base/test/scoped_mock_time_message_loop_task_runner.h

+// 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.
+
+#ifndef BASE_TEST_SCOPED_MOCK_TIME_MESSAGE_LOOP_TASK_RUNNER_H_
+#define BASE_TEST_SCOPED_MOCK_TIME_MESSAGE_LOOP_TASK_RUNNER_H_
+
+#include "base/macros.h"
+#include "base/memory/ref_counted.h"
+#include "base/test/test_mock_time_task_runner.h"
+
+namespace base {
+
+class SingleThreadTaskRunner;
+
+// A scoped wrapper around TestMockTimeTaskRunner that replaces
+// MessageLoop::current()'s task runner (and consequently
+// ThreadTaskRunnerHandle) with a TestMockTimeTaskRunner and resets it back at
+// the end of its scope.
+//
+// Note: RunLoop() will not work in the scope of a
+// ScopedMockTimeMessageLoopTaskRunner, the underlying TestMockTimeTaskRunner's
+// methods must be used instead to pump tasks.
+class ScopedMockTimeMessageLoopTaskRunner {
+ public:
+  ScopedMockTimeMessageLoopTaskRunner();
+  ~ScopedMockTimeMessageLoopTaskRunner();
+
+  TestMockTimeTaskRunner* task_runner() { return task_runner_.get(); }
+  TestMockTimeTaskRunner* operator->() { return task_runner_.get(); }
+
+ private:
+  const scoped_refptr<TestMockTimeTaskRunner> task_runner_;
+  scoped_refptr<SingleThreadTaskRunner> previous_task_runner_;
+
+  DISALLOW_COPY_AND_ASSIGN(ScopedMockTimeMessageLoopTaskRunner);
+};
+
+}  // namespace base
+
+#endif  // BASE_TEST_SCOPED_MOCK_TIME_MESSAGE_LOOP_TASK_RUNNER_H_