Add API to allow deducting bitrate from incoming estimates before the capacity is distributed among outgoing video streams. For example, this can be used to reserve space for audio streams.

BUG=
R=stefan@webrtc.org

Review URL: https://webrtc-codereview.appspot.com/10499004

git-svn-id: http://webrtc.googlecode.com/svn/trunk/webrtc@5791 4adac7df-926f-26a2-2b94-8c16560cd09d
diff --git a/video_engine/vie_channel_manager.h b/video_engine/vie_channel_manager.h
index a979ab6..240f1b1 100644
--- a/video_engine/vie_channel_manager.h
+++ b/video_engine/vie_channel_manager.h
@@ -75,6 +75,9 @@
   // Adds a channel to include when sending REMB.
   bool SetRembStatus(int channel_id, bool sender, bool receiver);
 
+  bool SetReservedTransmitBitrate(int channel_id,
+                                  uint32_t reserved_transmit_bitrate_bps);
+
   // Updates the SSRCs for a channel. If one of the SSRCs already is registered,
   // it will simply be ignored and no error is returned.
   void UpdateSsrcs(int channel_id, const std::list<unsigned int>& ssrcs);