Revert of Cast:Adding cast_transport_config and cleaning up

media/cast/cast_environment.cc

Index: media/cast/cast_environment.cc
diff --git a/media/cast/cast_environment.cc b/media/cast/cast_environment.cc
index 6b084b161565a79b02e7f1e651a551b1685f535d..eac83081b7c0c57ce741be2cd53edeca92acdd24 100644
--- a/media/cast/cast_environment.cc
+++ b/media/cast/cast_environment.cc
@@ -18,7 +18,6 @@
     scoped_refptr<TaskRunner> audio_decode_thread_proxy,
     scoped_refptr<TaskRunner> video_encode_thread_proxy,
     scoped_refptr<TaskRunner> video_decode_thread_proxy,
-    scoped_refptr<TaskRunner> transport_thread_proxy,
     const CastLoggingConfig& config)
     : clock_(clock),
       main_thread_proxy_(main_thread_proxy),
@@ -26,7 +25,6 @@
       audio_decode_thread_proxy_(audio_decode_thread_proxy),
       video_encode_thread_proxy_(video_encode_thread_proxy),
       video_decode_thread_proxy_(video_decode_thread_proxy),
-      transport_thread_proxy_(transport_thread_proxy),
       logging_(new LoggingImpl(main_thread_proxy, config)) {
   DCHECK(main_thread_proxy) << "Main thread required";
 }
@@ -65,8 +63,6 @@
       return video_encode_thread_proxy_;
     case CastEnvironment::VIDEO_DECODER:
       return video_decode_thread_proxy_;
-    case CastEnvironment::TRANSPORT:
-      return transport_thread_proxy_;
     default:
       NOTREACHED() << "Invalid Thread identifier";
       return NULL;
@@ -85,8 +81,6 @@
       return video_encode_thread_proxy_->RunsTasksOnCurrentThread();
     case CastEnvironment::VIDEO_DECODER:
       return video_decode_thread_proxy_->RunsTasksOnCurrentThread();
-    case CastEnvironment::TRANSPORT:
-      return transport_thread_proxy_->RunsTasksOnCurrentThread();
     default:
       NOTREACHED() << "Invalid thread identifier";
       return false;