Adding cbr support for Opus

webrtc/modules/audio_coding/include/audio_coding_module.h

Index: webrtc/modules/audio_coding/include/audio_coding_module.h
diff --git a/webrtc/modules/audio_coding/include/audio_coding_module.h b/webrtc/modules/audio_coding/include/audio_coding_module.h
index 1893b626de86dcbeb2809fef169ccb423b3fb4a4..ac739b0ca18680c5e16f79c97094053f8959c664 100644
--- a/webrtc/modules/audio_coding/include/audio_coding_module.h
+++ b/webrtc/modules/audio_coding/include/audio_coding_module.h
@@ -771,6 +771,27 @@ class AudioCodingModule {
   virtual int DisableOpusDtx() = 0;
 
   ///////////////////////////////////////////////////////////////////////////
+  // int EnableOpusCbr()
+  // Enable the CBR, if current send codec is Opus.
+  //
+  // Return value:
+  //   -1 if current send codec is not Opus or error occurred in enabling the
+  //      Opus CBR mode.
+  //    0 if Opus CBR is enabled successfully.
+  //
+  virtual int EnableOpusCbr() = 0;
+
+  ///////////////////////////////////////////////////////////////////////////
+  // int DisableOpusCbr()
+  // If current send codec is Opus, disables its internal CBR.
+  //
+  // Return value:
+  //   -1 if current send codec is not Opus or error occurred in disabling CBR.
+  //    0 if Opus CBR is disabled successfully.
+  //
+  virtual int DisableOpusCbr() = 0;
+
+  ///////////////////////////////////////////////////////////////////////////
   //   statistics
   //