Varispeed support for SincResampler.

media/base/multi_channel_resampler.h

Index: media/base/multi_channel_resampler.h
diff --git a/media/base/multi_channel_resampler.h b/media/base/multi_channel_resampler.h
index 6dd565b1b93a8ae17002db50c9f90695a6f0cba3..549ddea817f9c6c52455f4ddaca467b9f681de77 100644
--- a/media/base/multi_channel_resampler.h
+++ b/media/base/multi_channel_resampler.h
@@ -35,9 +35,15 @@ class MEDIA_EXPORT MultiChannelResampler {
   // Resamples |frames| of data from |read_cb_| into AudioBus.
   void Resample(AudioBus* audio_bus, int frames);
 
-  // Flush all buffered data and reset internal indices.
+  // Flush all buffered data and reset internal indices.  Not thread safe, do
+  // not call while Resample() is in progress.
   void Flush();
 
+  // Update ratio for all SincResamplers.  SetRatio() will cause reconstruction
+  // of the kernels used for resampling.  Not thread safe, do not call while
+  // Resample() is in progress.
+  void SetRatio(double io_sample_rate_ratio);
+
  private:
   // SincResampler::ReadCB implementation.  ProvideInput() will be called for
   // each channel (in channel order) as SincResampler needs more data.