Update API for Objective-C RTCMediaStream.

webrtc/api/BUILD.gn

Index: webrtc/api/BUILD.gn
diff --git a/webrtc/api/BUILD.gn b/webrtc/api/BUILD.gn
index 91449842570bf0d7f8bc799d5c751fc57207ad8d..1c333e4c77ae57f2512429acb9ee8c5ce2856619 100644
--- a/webrtc/api/BUILD.gn
+++ b/webrtc/api/BUILD.gn
@@ -29,15 +29,18 @@ if (is_ios) {
     ]
     sources = [
       # Add these when there's a BUILD.gn for peer connection APIs
-      #"objc/RTCAudioTrack+Private.h",
-      #"objc/RTCAudioTrack.h",
-      #"objc/RTCAudioTrack.mm",s
       #"objc/RTCAVFoundationVideoSource+Private.h",
       #"objc/RTCAVFoundationVideoSource.h",
       #"objc/RTCAVFoundationVideoSource.mm",
+      #"objc/RTCAudioTrack+Private.h",
+      #"objc/RTCAudioTrack.h",
+      #"objc/RTCAudioTrack.mm",
       #"objc/RTCIceCandidate+Private.h",
       #"objc/RTCIceCandidate.h",
       #"objc/RTCIceCandidate.mm",
+      #"objc/RTCMediaStream+Private.h",
+      #"objc/RTCMediaStream.h",
+      #"objc/RTCMediaStream.mm",
       #"objc/RTCMediaStreamTrack+Private.h",
       #"objc/RTCMediaStreamTrack.h",
       #"objc/RTCMediaStreamTrack.mm",