Compute RTCConnectionState and RTCIceConnectionState.

Compute these states in jseptransportController and store them. Eventually they should be passed on to the peer connection observer and exposed in the blink layer.

Bug: webrtc:9308
Change-Id: Ifdec39c24a607fcb8211c4acf6b9704eaff371b1
Reviewed-on: https://webrtc-review.googlesource.com/c/103506
Commit-Queue: Jonas Olsson <jonasolsson@webrtc.org>
Reviewed-by: Karl Wiberg <kwiberg@webrtc.org>
Reviewed-by: Steve Anton <steveanton@webrtc.org>
Reviewed-by: Harald Alvestrand <hta@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#25288}
diff --git a/pc/dtlssrtptransport.h b/pc/dtlssrtptransport.h
index 498f02e..cac560e 100644
--- a/pc/dtlssrtptransport.h
+++ b/pc/dtlssrtptransport.h
@@ -42,7 +42,8 @@
   void UpdateRecvEncryptedHeaderExtensionIds(
       const std::vector<int>& recv_extension_ids);
 
-  sigslot::signal2<DtlsSrtpTransport*, bool> SignalDtlsSrtpSetupFailure;
+  sigslot::signal<DtlsSrtpTransport*, bool> SignalDtlsSrtpSetupFailure;
+  sigslot::signal<> SignalDtlsStateChange;
 
   RTCError SetSrtpSendKey(const cricket::CryptoParams& params) override {
     return RTCError(RTCErrorType::UNSUPPORTED_OPERATION,