Avoid reporting 0 as input level when AudioProcessing zero out the audio data

content/renderer/media/media_stream_audio_level_calculator.h

Index: content/renderer/media/media_stream_audio_level_calculator.h
diff --git a/content/renderer/media/media_stream_audio_level_calculator.h b/content/renderer/media/media_stream_audio_level_calculator.h
index 41c9c34f7be1b2f803941ca2429417ddc8eb4fdc..3b4b2f6babfb6ad9811d8b224d3e44f74385c056 100644
--- a/content/renderer/media/media_stream_audio_level_calculator.h
+++ b/content/renderer/media/media_stream_audio_level_calculator.h
@@ -21,8 +21,14 @@ class MediaStreamAudioLevelCalculator {
 
   // Calculates the signal level of the audio data.
   // Returns the absolute value of the amplitude of the signal.
+  // |force_report_nonzero_energy| is a flag forcing the calculator to
+  // report nonzero energy. Since |audio_data| is post processed data, and the

[tommi (sloooow) - chröme, 2014/10/20 15:40:17]

// report nonzero energy even if the energy of the processed audio is zero.
<etc>

[no longer working on chromium, 2014/10/20 15:45:46]

Done.

+  // audio processing might zero all the audio data, when the caller detects
+  // the pre processed data contain energy, it could pass
+  // |force_report_nonzero_energy| as true to force calculator to report 1 as
+  // energy when |audio_data| is all zero.
   int Calculate(const int16* audio_data, int number_of_channels,
-                int number_of_frames);
+                int number_of_frames, bool force_report_nonzero_energy);
 
  private:
   // Used to DCHECK that the constructor and Calculate() are always called on