Replace WaitableEvents and ConditionalVariables in VideoRendererBase tests with MessageLoop.

media/base/mock_callback.h

-// Copyright (c) 2012 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 MEDIA_BASE_MOCK_CALLBACK_H_
-#define MEDIA_BASE_MOCK_CALLBACK_H_
-
-#include "base/callback.h"
-#include "media/base/pipeline_status.h"
-#include "testing/gmock/include/gmock/gmock.h"
-
-namespace media {
-
-// Utility mock for testing methods expecting Closures.  See
-// NewExpectedClosure() below for a helper suitable when expectation order is
-// not checked (or when the expectation can be set at mock construction time).
-class MockClosure : public base::RefCountedThreadSafe<MockClosure> {
- public:
-  MockClosure();
-  MOCK_METHOD0(Run, void());
-
- protected:
-  friend class base::RefCountedThreadSafe<MockClosure>;
-  virtual ~MockClosure();
-
- private:
-  DISALLOW_COPY_AND_ASSIGN(MockClosure);
-};
-
-// Return a callback that expects to be run once.
-base::Closure NewExpectedClosure();
-base::Callback<void(PipelineStatus)> NewExpectedStatusCB(PipelineStatus status);
-
-}  // namespace media
-
-#endif  // MEDIA_BASE_MOCK_CALLBACK_H_