Revert of Pick the DTLS handshake timeout based on the ICE RTT estimate

webrtc/p2p/base/icetransportinternal.h

Index: webrtc/p2p/base/icetransportinternal.h
diff --git a/webrtc/p2p/base/icetransportinternal.h b/webrtc/p2p/base/icetransportinternal.h
index 7dd1993a1b37eb954196880dcfa483c7b66933fa..0ac7974f1de92db2f2bdd74ffeb0d9c9f6820cb1 100644
--- a/webrtc/p2p/base/icetransportinternal.h
+++ b/webrtc/p2p/base/icetransportinternal.h
@@ -103,10 +103,6 @@
   // Returns the current stats for this connection.
   virtual bool GetStats(ConnectionInfos* infos) = 0;
 
-  // Returns RTT estimate over the currently active connection, or an empty
-  // rtc::Optional if there is none.
-  virtual rtc::Optional<int> GetRttEstimate() = 0;
-
   sigslot::signal1<IceTransportInternal*> SignalGatheringState;
 
   // Handles sending and receiving of candidates.