Change base::TickClock to a ref counted class.

content/browser/media/audio_stream_monitor_unittest.cc

Index: content/browser/media/audio_stream_monitor_unittest.cc
diff --git a/content/browser/media/audio_stream_monitor_unittest.cc b/content/browser/media/audio_stream_monitor_unittest.cc
index 8b55d8c8a99caf49d3ab2715b12f97a88a722c3c..e0758f4ac2929708b4369417324f0d37b6fca8a3 100644
--- a/content/browser/media/audio_stream_monitor_unittest.cc
+++ b/content/browser/media/audio_stream_monitor_unittest.cc
@@ -41,9 +41,10 @@ class MockWebContentsDelegate : public WebContentsDelegate {
 
 class AudioStreamMonitorTest : public RenderViewHostTestHarness {
  public:
-  AudioStreamMonitorTest() {
+  AudioStreamMonitorTest()
+      : monitor_(NULL), clock_(new base::SimpleTestTickClock()) {
     // Start |clock_| at non-zero.
-    clock_.Advance(base::TimeDelta::FromSeconds(1000000));
+    clock_->Advance(base::TimeDelta::FromSeconds(1000000));
   }
 
   virtual void SetUp() override {
@@ -53,12 +54,12 @@ class AudioStreamMonitorTest : public RenderViewHostTestHarness {
         RenderViewHostTestHarness::web_contents());
     web_contents->SetDelegate(&mock_web_contents_delegate_);
     monitor_ = web_contents->audio_stream_monitor();
-    const_cast<base::TickClock*&>(monitor_->clock_) = &clock_;
+    monitor_->set_clock_for_testing(clock_);
   }
 
-  base::TimeTicks GetTestClockTime() { return clock_.NowTicks(); }
+  base::TimeTicks GetTestClockTime() { return clock_->NowTicks(); }
 
-  void AdvanceClock(const base::TimeDelta& delta) { clock_.Advance(delta); }
+  void AdvanceClock(const base::TimeDelta& delta) { clock_->Advance(delta); }
 
   AudioStreamMonitor::ReadPowerAndClipCallback CreatePollCallback(
       int stream_id) {
@@ -143,7 +144,7 @@ class AudioStreamMonitorTest : public RenderViewHostTestHarness {
   }
 
   MockWebContentsDelegate mock_web_contents_delegate_;
-  base::SimpleTestTickClock clock_;
+  scoped_refptr<base::SimpleTestTickClock> clock_;
   std::map<int, float> current_power_;
 
   DISALLOW_COPY_AND_ASSIGN(AudioStreamMonitorTest);