Compile fix for gcc 4.6 (unused variable).

content/renderer/media/audio_renderer_impl.cc

Index: content/renderer/media/audio_renderer_impl.cc
diff --git a/content/renderer/media/audio_renderer_impl.cc b/content/renderer/media/audio_renderer_impl.cc
index 768142ad5ee726b8b777cb577252724eebc588ea..d9468570b41f25fc63f2c3631f53d8ec268fbe5d 100644
--- a/content/renderer/media/audio_renderer_impl.cc
+++ b/content/renderer/media/audio_renderer_impl.cc
@@ -203,8 +203,6 @@ void AudioRendererImpl::Render(const std::vector<float*>& audio_data,
   }
 
   // Adjust the playback delay.
-  base::Time current_time = base::Time::Now();
-
   base::TimeDelta request_delay =
       base::TimeDelta::FromMilliseconds(audio_delay_milliseconds);