Fix some warnings in ObjC code.

webrtc/api/objc/RTCIceCandidate.h

Index: webrtc/api/objc/RTCIceCandidate.h
diff --git a/webrtc/api/objc/RTCIceCandidate.h b/webrtc/api/objc/RTCIceCandidate.h
index 41ea69e9912a59e6417b9bde7c20cd3326066afa..e521ae04f6d3d444e6f38f2daa2089176b87007d 100644
--- a/webrtc/api/objc/RTCIceCandidate.h
+++ b/webrtc/api/objc/RTCIceCandidate.h
@@ -24,7 +24,7 @@ NS_ASSUME_NONNULL_BEGIN
  * The index (starting at zero) of the media description this candidate is
  * associated with in the SDP.
  */
-@property(nonatomic, readonly) NSInteger sdpMLineIndex;
+@property(nonatomic, readonly) int sdpMLineIndex;
 
 /** The SDP string for this candidate. */
 @property(nonatomic, readonly) NSString *sdp;
@@ -35,7 +35,7 @@ NS_ASSUME_NONNULL_BEGIN
  * Initialize an RTCIceCandidate from SDP.
  */
 - (instancetype)initWithSdp:(NSString *)sdp
-              sdpMLineIndex:(NSInteger)sdpMLineIndex
+              sdpMLineIndex:(int)sdpMLineIndex
                      sdpMid:(nullable NSString *)sdpMid
     NS_DESIGNATED_INITIALIZER;