Update iOS AppRTCDemo to use the updated Objective-C API.

webrtc/examples/objc/AppRTCDemo/ARDAppClient.h

Index: webrtc/examples/objc/AppRTCDemo/ARDAppClient.h
diff --git a/webrtc/examples/objc/AppRTCDemo/ARDAppClient.h b/webrtc/examples/objc/AppRTCDemo/ARDAppClient.h
index 0745c16a4c58bc3e79dea9b31b7356d809d86c9d..b59838e3cc6bfee41f176299c73c8b638d5ab754 100644
--- a/webrtc/examples/objc/AppRTCDemo/ARDAppClient.h
+++ b/webrtc/examples/objc/AppRTCDemo/ARDAppClient.h
@@ -9,8 +9,8 @@
  */
 
 #import <Foundation/Foundation.h>
-
-#import "RTCVideoTrack.h"
+#import "webrtc/api/objc/RTCPeerConnection.h"
+#import "webrtc/api/objc/RTCVideoTrack.h"
 
 typedef NS_ENUM(NSInteger, ARDAppClientState) {
   // Disconnected from servers.
@@ -30,7 +30,7 @@ typedef NS_ENUM(NSInteger, ARDAppClientState) {
     didChangeState:(ARDAppClientState)state;
 
 - (void)appClient:(ARDAppClient *)client
-    didChangeConnectionState:(RTCICEConnectionState)state;
+    didChangeConnectionState:(RTCIceConnectionState)state;
 
 - (void)appClient:(ARDAppClient *)client
     didReceiveLocalVideoTrack:(RTCVideoTrack *)localVideoTrack;