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

webrtc/voice_engine/voice_engine_impl.h

Index: webrtc/voice_engine/voice_engine_impl.h
diff --git a/webrtc/voice_engine/voice_engine_impl.h b/webrtc/voice_engine/voice_engine_impl.h
index c3b2e5ced926d705640006cd4942230c65d0e57b..014322ba078b788e600ab704f54ad9af4beb7f4a 100644
--- a/webrtc/voice_engine/voice_engine_impl.h
+++ b/webrtc/voice_engine/voice_engine_impl.h
@@ -48,6 +48,9 @@
 #endif
 
 namespace webrtc {
+namespace voe {
+class ChannelProxy;
+}  // namespace voe
 
 class VoiceEngineImpl : public voe::SharedData,  // Must be the first base class
                         public VoiceEngine,
@@ -128,6 +131,10 @@ class VoiceEngineImpl : public voe::SharedData,  // Must be the first base class
   // This implements the Release() method for all the inherited interfaces.
   int Release() override;
 
+  // Backdoor to access a voe::Channel object without a channel ID. This is only
+  // to be used while refactoring the VoE API!
+  virtual voe::ChannelProxy* GetChannelProxy(int channel_id);
+
  // This is *protected* so that FakeVoiceEngine can inherit from the class and
  // manipulate the reference count. See: fake_voice_engine.h.
  protected: