Change base::TickClock to a ref counted class.

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 f22f0a4eca220bf1041baa3467ec0192f8f6f75a..d897d9a46d280726450d284c5046bdde41edcc2c 100644
--- a/media/cast/cast_environment.cc
+++ b/media/cast/cast_environment.cc
@@ -22,15 +22,16 @@ namespace media {
 namespace cast {
 
 CastEnvironment::CastEnvironment(
-    scoped_ptr<base::TickClock> clock,
+    scoped_refptr<base::TickClock> clock,
     scoped_refptr<SingleThreadTaskRunner> main_thread_proxy,
     scoped_refptr<SingleThreadTaskRunner> audio_thread_proxy,
     scoped_refptr<SingleThreadTaskRunner> video_thread_proxy)
     : main_thread_proxy_(main_thread_proxy),
       audio_thread_proxy_(audio_thread_proxy),
       video_thread_proxy_(video_thread_proxy),
-      clock_(clock.Pass()),
-      logging_(new LoggingImpl) {}
+      clock_(clock),
+      logging_(new LoggingImpl) {
+}
 
 CastEnvironment::~CastEnvironment() {
   // Logging must be deleted on the main thread.