Don't return wall clock times when time isn't ticking.

media/renderers/audio_renderer_impl_unittest.cc

Index: media/renderers/audio_renderer_impl_unittest.cc
diff --git a/media/renderers/audio_renderer_impl_unittest.cc b/media/renderers/audio_renderer_impl_unittest.cc
index 1fe5bdd0a8b3a1e238610a0c2720b4000cccfee2..119fb76b464915a3cd8ed0d432f2c3d211c30a74 100644
--- a/media/renderers/audio_renderer_impl_unittest.cc
+++ b/media/renderers/audio_renderer_impl_unittest.cc
@@ -519,6 +519,10 @@ TEST_F(AudioRendererImplTest, Underflow_Flush) {
   WaitForPendingRead();
   StopTicking();
 
+  // After time stops ticking wall clock times should not be returned.
+  EXPECT_FALSE(
+      renderer_->GetWallClockTimes(std::vector<base::TimeDelta>(1), nullptr));
+
   // We shouldn't expect another buffering state change when flushing.
   FlushDuringPendingRead();
 }