Reland of "Remove the obsolete enum webrtc::PeerConnectionInterface::IceState." (patchset #1 id:1 of https://codereview.webrtc.org/2402993002/ )

Reason for revert:
Upstream fixes landed.

Original issue's description:
> Revert of "Remove the obsolete enum webrtc::PeerConnectionInterface::IceState." (patchset #1 id:1 of https://codereview.webrtc.org/2361053003/ )
>
> Reason for revert:
> Breaks upstream code.
>
> Original issue's description:
> > Reland of "Remove the obsolete enum webrtc::PeerConnectionInterface::IceState."
> >
> > Original commit https://codereview.webrtc.org/2256663002
> > was reverted by https://codereview.webrtc.org/2290963002 .
> >
> > BUG=webrtc:6299
> > TBR=pthatcher@webrtc.org
> >
> > Committed: https://crrev.com/fc9414ab513941028309d15a2baf711ef38f93a7
> > Cr-Commit-Position: refs/heads/master@{#14584}
>
> TBR=pthatcher@webrtc.org,johan@webrtc.org
> # Skipping CQ checks because original CL landed less than 1 days ago.
> NOPRESUBMIT=true
> NOTREECHECKS=true
> NOTRY=true
> BUG=webrtc:6299
>
> Committed: https://crrev.com/57cb873707fbcc4864f0ee98129f73e7bef26c1a
> Cr-Commit-Position: refs/heads/master@{#14586}

TBR=pthatcher@webrtc.org,johan@webrtc.org
# Not skipping CQ checks because original CL landed more than 1 days ago.
BUG=webrtc:6299

Review-Url: https://codereview.webrtc.org/2411673005
Cr-Commit-Position: refs/heads/master@{#14602}
diff --git a/webrtc/api/peerconnection.cc b/webrtc/api/peerconnection.cc
index dd99e36..830c301 100644
--- a/webrtc/api/peerconnection.cc
+++ b/webrtc/api/peerconnection.cc
@@ -570,7 +570,6 @@
       observer_(NULL),
       uma_observer_(NULL),
       signaling_state_(kStable),
-      ice_state_(kIceNew),
       ice_connection_state_(kIceConnectionNew),
       ice_gathering_state_(kIceGatheringNew),
       event_log_(RtcEventLog::Create(webrtc::Clock::GetRealTimeClock())),
@@ -901,10 +900,6 @@
   return signaling_state_;
 }
 
-PeerConnectionInterface::IceState PeerConnection::ice_state() {
-  return ice_state_;
-}
-
 PeerConnectionInterface::IceConnectionState
 PeerConnection::ice_connection_state() {
   return ice_connection_state_;
diff --git a/webrtc/api/peerconnection.h b/webrtc/api/peerconnection.h
index f5b0af8..7409585 100644
--- a/webrtc/api/peerconnection.h
+++ b/webrtc/api/peerconnection.h
@@ -108,8 +108,6 @@
 
   SignalingState signaling_state() override;
 
-  // TODO(bemasc): Remove ice_state() when callers are removed.
-  IceState ice_state() override;
   IceConnectionState ice_connection_state() override;
   IceGatheringState ice_gathering_state() override;
 
@@ -387,8 +385,6 @@
   PeerConnectionObserver* observer_;
   UMAObserver* uma_observer_;
   SignalingState signaling_state_;
-  // TODO(bemasc): Remove ice_state_.
-  IceState ice_state_;
   IceConnectionState ice_connection_state_;
   IceGatheringState ice_gathering_state_;
 
diff --git a/webrtc/api/peerconnectioninterface.h b/webrtc/api/peerconnectioninterface.h
index a04e53e..ea056bf 100644
--- a/webrtc/api/peerconnectioninterface.h
+++ b/webrtc/api/peerconnectioninterface.h
@@ -152,19 +152,6 @@
     kClosed,
   };
 
-  // TODO(bemasc): Remove IceState when callers are changed to
-  // IceConnection/GatheringState.
-  enum IceState {
-    kIceNew,
-    kIceGathering,
-    kIceWaiting,
-    kIceChecking,
-    kIceConnected,
-    kIceCompleted,
-    kIceFailed,
-    kIceClosed,
-  };
-
   enum IceGatheringState {
     kIceGatheringNew,
     kIceGatheringGathering,
@@ -522,14 +509,6 @@
 
   // Returns the current SignalingState.
   virtual SignalingState signaling_state() = 0;
-
-  // TODO(bemasc): Remove ice_state when callers are changed to
-  // IceConnection/GatheringState.
-  // Returns the current IceState.
-  virtual IceState ice_state() {
-      RTC_NOTREACHED();
-    return kIceNew;
-  }
   virtual IceConnectionState ice_connection_state() = 0;
   virtual IceGatheringState ice_gathering_state() = 0;
 
diff --git a/webrtc/api/peerconnectionproxy.h b/webrtc/api/peerconnectionproxy.h
index 8c15b3d..8cd3a48 100644
--- a/webrtc/api/peerconnectionproxy.h
+++ b/webrtc/api/peerconnectionproxy.h
@@ -72,7 +72,6 @@
                 const std::vector<cricket::Candidate>&);
   PROXY_METHOD1(void, RegisterUMAObserver, UMAObserver*)
   PROXY_METHOD0(SignalingState, signaling_state)
-  PROXY_METHOD0(IceState, ice_state)
   PROXY_METHOD0(IceConnectionState, ice_connection_state)
   PROXY_METHOD0(IceGatheringState, ice_gathering_state)
   PROXY_METHOD2(bool, StartRtcEventLog, rtc::PlatformFile, int64_t)