Update ice server provider response format in iOS AppRTCMobile

webrtc/examples/objc/AppRTCMobile/RTCIceServer+JSON.m

 /*
  *  Copyright 2014 The WebRTC Project Authors. All rights reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
 #import "RTCIceServer+JSON.h"
 
-static NSString const *kRTCICEServerUsernameKey = @"username";
-static NSString const *kRTCICEServerPasswordKey = @"password";
-static NSString const *kRTCICEServerUrisKey = @"uris";
-static NSString const *kRTCICEServerUrlKey = @"urls";
-static NSString const *kRTCICEServerCredentialKey = @"credential";
-
 @implementation RTCIceServer (JSON)
 
 + (RTCIceServer *)serverFromJSONDictionary:(NSDictionary *)dictionary {
-  NSString *url = dictionary[kRTCICEServerUrlKey];
-  NSString *username = dictionary[kRTCICEServerUsernameKey];
-  NSString *credential = dictionary[kRTCICEServerCredentialKey];
-  username = username ? username : @"";
-  credential = credential ? credential : @"";
-  return [[RTCIceServer alloc] initWithURLStrings:@[url]
+  NSArray *turnUrls = dictionary[@"urls"];
+  NSString *username = dictionary[@"username"] ?: @"";
+  NSString *credential = dictionary[@"credential"] ?: @"";
+  return [[RTCIceServer alloc] initWithURLStrings:turnUrls
                                          username:username
                                        credential:credential];
 }
 
-+ (RTCIceServer *)serverFromCEODJSONDictionary:(NSDictionary *)dictionary {
-  NSString *username = dictionary[kRTCICEServerUsernameKey];
-  NSString *password = dictionary[kRTCICEServerPasswordKey];
-  NSArray *uris = dictionary[kRTCICEServerUrisKey];
-  RTCIceServer *server =
-      [[RTCIceServer alloc] initWithURLStrings:uris
-                                      username:username
-                                    credential:password];
-  return server;
-}
-
 @end