Change base::TickClock to a ref counted class.

chrome/browser/media/cast_transport_host_filter.cc

Index: chrome/browser/media/cast_transport_host_filter.cc
diff --git a/chrome/browser/media/cast_transport_host_filter.cc b/chrome/browser/media/cast_transport_host_filter.cc
index 3f7739d506a0523a75f46b7431a6b15ca5e2b961..6cc30cfa8b9a212e02d0a3c817f628b7ab7d5b00 100644
--- a/chrome/browser/media/cast_transport_host_filter.cc
+++ b/chrome/browser/media/cast_transport_host_filter.cc
@@ -4,6 +4,7 @@
 
 #include "chrome/browser/media/cast_transport_host_filter.h"
 
+#include "base/time/default_tick_clock.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/net/chrome_net_log.h"
 #include "content/public/browser/power_save_blocker.h"
@@ -20,7 +21,9 @@ namespace cast {
 
 CastTransportHostFilter::CastTransportHostFilter()
     : BrowserMessageFilter(CastMsgStart),
-      weak_factory_(this) {}
+      clock_(new base::DefaultTickClock),
+      weak_factory_(this) {
+}
 
 CastTransportHostFilter::~CastTransportHostFilter() {}
 
@@ -91,7 +94,7 @@ void CastTransportHostFilter::OnNew(
   scoped_ptr<media::cast::CastTransportSender> sender =
       media::cast::CastTransportSender::Create(
           g_browser_process->net_log(),
-          &clock_,
+          clock_.get(),
           remote_end_point,
           make_scoped_ptr(options.DeepCopy()),
           base::Bind(&CastTransportHostFilter::NotifyStatusChange,