Pass around the candidate removals events in IOS clients

webrtc/examples/objc/AppRTCDemo/ARDAppClient.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.
  */
 
@@ skipping 312 matching lines @@
     didReceiveMessage:(ARDSignalingMessage *)message {
   switch (message.type) {
     case kARDSignalingMessageTypeOffer:
     case kARDSignalingMessageTypeAnswer:
       // Offers and answers must be processed before any other message, so we
       // place them at the front of the queue.
       _hasReceivedSdp = YES;
       [_messageQueue insertObject:message atIndex:0];
       break;
     case kARDSignalingMessageTypeCandidate:
+    case kARDSignalingMessageTypeCandidateRemoval:
       [_messageQueue addObject:message];
       break;
     case kARDSignalingMessageTypeBye:
       // Disconnects can be processed immediately.
       [self processSignalingMessage:message];
       return;
   }
   [self drainMessageQueueIfReady];
 }
 
@@ skipping 60 matching lines @@
 - (void)peerConnection:(RTCPeerConnection *)peerConnection
     didGenerateIceCandidate:(RTCIceCandidate *)candidate {
   dispatch_async(dispatch_get_main_queue(), ^{
     ARDICECandidateMessage *message =
         [[ARDICECandidateMessage alloc] initWithCandidate:candidate];
     [self sendSignalingMessage:message];
   });
 }
 
 - (void)peerConnection:(RTCPeerConnection *)peerConnection
+    didRemoveIceCandidates:(NSArray<RTCIceCandidate *> *)candidates {
+  dispatch_async(dispatch_get_main_queue(), ^{
+    ARDICECandidateRemovalMessage *message =
+        [[ARDICECandidateRemovalMessage alloc]
+            initWithRemovedCandidates:candidates];
+    [self sendSignalingMessage:message];
+  });
+}
+
+- (void)peerConnection:(RTCPeerConnection *)peerConnection
     didOpenDataChannel:(RTCDataChannel *)dataChannel {
 }
 
 #pragma mark - RTCSessionDescriptionDelegate
 // Callbacks for this delegate occur on non-main thread and need to be
 // dispatched back to main queue as needed.
 
 - (void)peerConnection:(RTCPeerConnection *)peerConnection
     didCreateSessionDescription:(RTCSessionDescription *)sdp
                           error:(NSError *)error {
@@ skipping 143 matching lines @@
             didSetSessionDescriptionWithError:error];
       }];
       break;
     }
     case kARDSignalingMessageTypeCandidate: {
       ARDICECandidateMessage *candidateMessage =
           (ARDICECandidateMessage *)message;
       [_peerConnection addIceCandidate:candidateMessage.candidate];
       break;
     }
+    case kARDSignalingMessageTypeCandidateRemoval: {
+      ARDICECandidateRemovalMessage *candidateMessage =
+          (ARDICECandidateRemovalMessage *)message;
+      [_peerConnection removeIceCandidates:candidateMessage.candidates];
+      break;
+    }
     case kARDSignalingMessageTypeBye:
       // Other client disconnected.
       // TODO(tkchin): support waiting in room for next client. For now just
       // disconnect.
       [self disconnect];
       break;
   }
 }
 
 // Sends a signaling message to the other client. The caller will send messages
@@ skipping 186 matching lines @@
                                          code:kARDAppClientErrorInvalidRoom
                                      userInfo:@{
         NSLocalizedDescriptionKey: @"Invalid room.",
       }];
       break;
   }
   return error;
 }
 
 @end