Add experimental noise suppression dummy API.

Add this flag to the voe_cmd_test.

R=andrew@webrtc.org

Review URL: https://webrtc-codereview.appspot.com/3879004

git-svn-id: http://webrtc.googlecode.com/svn/trunk@5134 4adac7df-926f-26a2-2b94-8c16560cd09d
diff --git a/webrtc/modules/audio_processing/audio_processing_impl.h b/webrtc/modules/audio_processing/audio_processing_impl.h
index b0afd6d..6c22878 100644
--- a/webrtc/modules/audio_processing/audio_processing_impl.h
+++ b/webrtc/modules/audio_processing/audio_processing_impl.h
@@ -59,6 +59,10 @@
   virtual int Initialize() OVERRIDE;
   virtual int InitializeLocked();
   virtual void SetExtraOptions(const Config& config) OVERRIDE;
+  virtual int EnableExperimentalNs(bool enable) OVERRIDE;
+  virtual bool experimental_ns_enabled() const OVERRIDE {
+    return false;
+  }
   virtual int set_sample_rate_hz(int rate) OVERRIDE;
   virtual int sample_rate_hz() const OVERRIDE;
   virtual int set_num_channels(int input_channels,