Revert of Remove the obsolete enum webrtc::PeerConnectionInterface::IceState.

webrtc/api/peerconnection.cc

Index: webrtc/api/peerconnection.cc
diff --git a/webrtc/api/peerconnection.cc b/webrtc/api/peerconnection.cc
index c493f40c9ce87ae35b0096aea4e156e5c70c73f2..c675015ac9bbee705038fa997b716571eb342357 100644
--- a/webrtc/api/peerconnection.cc
+++ b/webrtc/api/peerconnection.cc
@@ -568,6 +568,7 @@
       observer_(NULL),
       uma_observer_(NULL),
       signaling_state_(kStable),
+      ice_state_(kIceNew),
       ice_connection_state_(kIceConnectionNew),
       ice_gathering_state_(kIceGatheringNew),
       rtcp_cname_(GenerateRtcpCname()),
@@ -885,6 +886,10 @@
 
 PeerConnectionInterface::SignalingState PeerConnection::signaling_state() {
   return signaling_state_;
+}
+
+PeerConnectionInterface::IceState PeerConnection::ice_state() {
+  return ice_state_;
 }
 
 PeerConnectionInterface::IceConnectionState