Open backdoor in VoiceEngineImpl to get at the actual voe::Channel objects from an ID.

webrtc/audio/audio_send_stream.h

Index: webrtc/audio/audio_send_stream.h
diff --git a/webrtc/audio/audio_send_stream.h b/webrtc/audio/audio_send_stream.h
index a4eb89d169e8177f1d472d5d333f8e3c86a0bfa4..b670efee3cbfad5074cbbc77050ed7e590f5230f 100644
--- a/webrtc/audio/audio_send_stream.h
+++ b/webrtc/audio/audio_send_stream.h
@@ -14,13 +14,16 @@
 #include "webrtc/audio_send_stream.h"
 #include "webrtc/audio_state.h"
 #include "webrtc/base/thread_checker.h"
+#include "webrtc/base/scoped_ptr.h"
 
 namespace webrtc {
-
 class VoiceEngine;
 
-namespace internal {
+namespace voe {
+class ChannelProxy;
+}  // namespace voe
 
+namespace internal {
 class AudioSendStream final : public webrtc::AudioSendStream {
  public:
   AudioSendStream(const webrtc::AudioSendStream::Config& config,
@@ -44,6 +47,7 @@ class AudioSendStream final : public webrtc::AudioSendStream {
   rtc::ThreadChecker thread_checker_;
   const webrtc::AudioSendStream::Config config_;
   rtc::scoped_refptr<webrtc::AudioState> audio_state_;
+  rtc::scoped_ptr<voe::ChannelProxy> channel_proxy_;
 
   RTC_DISALLOW_IMPLICIT_CONSTRUCTORS(AudioSendStream);
 };