Add a Clock and TickClock interface for mocking out time

media/base/pipeline.cc

 // 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.
 
 #include "media/base/pipeline.h"
 
 #include <algorithm>
 
 #include "base/bind.h"
 #include "base/callback.h"
@@ skipping 54 matching lines @@
 Pipeline::Pipeline(const scoped_refptr<base::MessageLoopProxy>& message_loop,
                    MediaLog* media_log)
     : message_loop_(message_loop),
       media_log_(media_log),
       running_(false),
       did_loading_progress_(false),
       total_bytes_(0),
       natural_size_(0, 0),
       volume_(1.0f),
       playback_rate_(0.0f),
-      clock_(new Clock(&base::Time::Now)),
+      clock_(new Clock(&default_clock_)),
       waiting_for_clock_update_(false),
       status_(PIPELINE_OK),
       has_audio_(false),
       has_video_(false),
       state_(kCreated),
       audio_ended_(false),
       video_ended_(false),
       audio_disabled_(false),
       creation_time_(base::Time::Now()) {
   media_log_->AddEvent(media_log_->CreatePipelineStateChangedEvent(kCreated));
@@ skipping 859 matching lines @@
 void Pipeline::StartClockIfWaitingForTimeUpdate_Locked() {
   lock_.AssertAcquired();
   if (!waiting_for_clock_update_)
     return;
 
   waiting_for_clock_update_ = false;
   clock_->Play();
 }
 
 }  // namespace media