Revert of - Clean up unused voice engine DTMF code.

webrtc/voice_engine/channel_proxy.cc

Index: webrtc/voice_engine/channel_proxy.cc
diff --git a/webrtc/voice_engine/channel_proxy.cc b/webrtc/voice_engine/channel_proxy.cc
index 10c88212024aa2ea911c09ccb97bcb2fd15ca65e..da7864f15feed7f7e58d0fb780c27c40453d37d8 100644
--- a/webrtc/voice_engine/channel_proxy.cc
+++ b/webrtc/voice_engine/channel_proxy.cc
@@ -148,9 +148,11 @@
   return channel()->SetSendTelephoneEventPayloadType(payload_type) == 0;
 }
 
-bool ChannelProxy::SendTelephoneEventOutband(int event, int duration_ms) {
+bool ChannelProxy::SendTelephoneEventOutband(uint8_t event,
+                                             uint32_t duration_ms) {
   RTC_DCHECK(thread_checker_.CalledOnValidThread());
-  return channel()->SendTelephoneEventOutband(event, duration_ms) == 0;
+  return
+      channel()->SendTelephoneEventOutband(event, duration_ms, 10, false) == 0;
 }
 
 void ChannelProxy::SetSink(std::unique_ptr<AudioSinkInterface> sink) {