Use enum instead of string in MessageLoopFactory::GetMessageLoop*

webkit/media/webmediaplayer_impl.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 "webkit/media/webmediaplayer_impl.h"
 
 #include <limits>
 #include <string>
 #include <vector>
 
@@ skipping 119 matching lines @@
       accelerated_compositing_reported_(false),
       incremented_externally_allocated_memory_(false),
       audio_source_provider_(audio_source_provider),
       audio_renderer_sink_(audio_renderer_sink),
       is_local_source_(false),
       decryptor_(proxy_.get(), client, frame) {
   media_log_->AddEvent(
       media_log_->CreateEvent(media::MediaLogEvent::WEBMEDIAPLAYER_CREATED));
 
   MessageLoop* pipeline_message_loop =
-      message_loop_factory_->GetMessageLoop("PipelineThread");
+      message_loop_factory_->GetMessageLoop(
+          media::MessageLoopFactory::PIPELINE);
   pipeline_ = new media::Pipeline(pipeline_message_loop, media_log_);
 
   // Let V8 know we started new thread if we did not did it yet.
   // Made separate task to avoid deletion of player currently being created.
   // Also, delaying GC until after player starts gets rid of starting lag --
   // collection happens in parallel with playing.
   //
   // TODO(enal): remove when we get rid of per-audio-stream thread.
   MessageLoop::current()->PostTask(
       FROM_HERE,
@@ skipping 874 matching lines @@
   return audio_source_provider_;
 }
 
 void WebMediaPlayerImpl::IncrementExternallyAllocatedMemory() {
   DCHECK_EQ(main_loop_, MessageLoop::current());
   incremented_externally_allocated_memory_ = true;
   v8::V8::AdjustAmountOfExternalAllocatedMemory(kPlayerExtraMemory);
 }
 
 }  // namespace webkit_media