Objective C API to read and set RtpParameters

webrtc/api/objc/RTCMediaStreamTrack.mm

Index: webrtc/api/objc/RTCMediaStreamTrack.mm
diff --git a/webrtc/api/objc/RTCMediaStreamTrack.mm b/webrtc/api/objc/RTCMediaStreamTrack.mm
index 25979b38d9a32bd968d531bdc66a5553ec77f4d7..14a84689086b72a77d45546655facef32f7ba686 100644
--- a/webrtc/api/objc/RTCMediaStreamTrack.mm
+++ b/webrtc/api/objc/RTCMediaStreamTrack.mm
@@ -64,6 +64,22 @@
   return self;
 }
 
+- (instancetype)initWithNativeTrack:
+    (rtc::scoped_refptr<webrtc::MediaStreamTrackInterface>)nativeTrack {
+  NSParameterAssert(nativeTrack);
+  if (nativeTrack->kind() ==
+      std::string(webrtc::MediaStreamTrackInterface::kAudioKind)) {
+    return [self initWithNativeTrack:nativeTrack
+                                type:RTCMediaStreamTrackTypeAudio];
+  }
+  if (nativeTrack->kind() ==
+      std::string(webrtc::MediaStreamTrackInterface::kVideoKind)) {
+    return [self initWithNativeTrack:nativeTrack
+                                type:RTCMediaStreamTrackTypeVideo];
+  }
+  return nil;
+}
+
 + (webrtc::MediaStreamTrackInterface::TrackState)nativeTrackStateForState:
     (RTCMediaStreamTrackState)state {
   switch (state) {