Upgrade Pipeline::Start() NOTREACHED() back into a CHECK().

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 92 matching lines @@
 
   media_log_->AddEvent(
       media_log_->CreateEvent(MediaLogEvent::PIPELINE_DESTROYED));
 }
 
 void Pipeline::Start(scoped_ptr<FilterCollection> collection,
                      const PipelineStatusCB& ended_cb,
                      const PipelineStatusCB& error_cb,
                      const PipelineStatusCB& start_cb) {
   base::AutoLock auto_lock(lock_);
-  if (running_) {
-    NOTREACHED() << "Media pipeline is already running";
-    return;
-  }
+  CHECK(!running_) << "Media pipeline is already running";
 
   running_ = true;
   message_loop_->PostTask(FROM_HERE, base::Bind(
       &Pipeline::StartTask, this, base::Passed(&collection),
       ended_cb, error_cb, start_cb));
 }
 
 void Pipeline::Stop(const base::Closure& stop_cb) {
   base::AutoLock auto_lock(lock_);
   message_loop_->PostTask(FROM_HERE, base::Bind(
@@ skipping 422 matching lines @@
   statistics_.video_bytes_decoded += stats.video_bytes_decoded;
   statistics_.video_frames_decoded += stats.video_frames_decoded;
   statistics_.video_frames_dropped += stats.video_frames_dropped;
 }
 
 void Pipeline::StartTask(scoped_ptr<FilterCollection> filter_collection,
                          const PipelineStatusCB& ended_cb,
                          const PipelineStatusCB& error_cb,
                          const PipelineStatusCB& start_cb) {
   DCHECK(message_loop_->BelongsToCurrentThread());
-  DCHECK_EQ(kCreated, state_);
+  CHECK_EQ(kCreated, state_)
+      << "Media pipeline cannot be started more than once";
+
   filter_collection_ = filter_collection.Pass();
   ended_cb_ = ended_cb;
   error_cb_ = error_cb;
   seek_cb_ = start_cb;
 
   // Kick off initialization.
   pipeline_init_state_.reset(new PipelineInitState());
 
   SetState(kInitDemuxer);
   InitializeDemuxer();
@@ skipping 647 matching lines @@
 void Pipeline::StartClockIfWaitingForTimeUpdate_Locked() {
   lock_.AssertAcquired();
   if (!waiting_for_clock_update_)
     return;
 
   waiting_for_clock_update_ = false;
   clock_->Play();
 }
 
 }  // namespace media