Allow remote fingerprint update during a call

webrtc/p2p/base/transportchannel.h

Index: webrtc/p2p/base/transportchannel.h
diff --git a/webrtc/p2p/base/transportchannel.h b/webrtc/p2p/base/transportchannel.h
index de0bd45a259f8d94b76404c8f190fc3fa2f638a1..b91af139b7155d35589305deef52cb0bb7308eb5 100644
--- a/webrtc/p2p/base/transportchannel.h
+++ b/webrtc/p2p/base/transportchannel.h
@@ -79,8 +79,9 @@ class TransportChannel : public sigslot::has_slots<> {
   // Emitted when the TransportChannel's ability to send has changed.
   sigslot::signal1<TransportChannel*> SignalReadyToSend;
   sigslot::signal1<TransportChannel*> SignalReceivingState;
-  // Emitted when the DtlsTransportState has changed.
-  sigslot::signal1<TransportChannel*> SignalDtlsState;
+  // Emitted whenever DTLS-SRTP is setup which will require setting up a new
+  // SRTP context.
+  sigslot::signal2<TransportChannel*, DtlsTransportState> SignalDtlsState;
 
   // Attempts to send the given packet.  The return value is < 0 on failure.
   // TODO: Remove the default argument once channel code is updated.