Add a lot of Pipeline tests to cover stopping/error handling while in a variety of states.

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 242 matching lines @@
 
 PipelineStatistics Pipeline::GetStatistics() const {
   base::AutoLock auto_lock(lock_);
   return statistics_;
 }
 
 void Pipeline::SetClockForTesting(Clock* clock) {
   clock_.reset(clock);
 }
 
+void Pipeline::SetErrorForTesting(PipelineStatus status) {
+  SetError(status);
+}
+
 void Pipeline::SetState(State next_state) {
   if (state_ != kStarted && next_state == kStarted &&
       !creation_time_.is_null()) {
     UMA_HISTOGRAM_TIMES(
         "Media.TimeToPipelineStarted", base::Time::Now() - creation_time_);
     creation_time_ = base::Time();
   }
   state_ = next_state;
   media_log_->AddEvent(media_log_->CreatePipelineStateChangedEvent(next_state));
 }
@@ skipping 1022 matching lines @@
 void Pipeline::StartClockIfWaitingForTimeUpdate_Locked() {
   lock_.AssertAcquired();
   if (!waiting_for_clock_update_)
     return;
 
   waiting_for_clock_update_ = false;
   clock_->Play();
 }
 
 }  // namespace media