Tweaks for new Objective-C API.

webrtc/api/objc/RTCVideoTrack.mm

Index: webrtc/api/objc/RTCVideoTrack.mm
diff --git a/webrtc/api/objc/RTCVideoTrack.mm b/webrtc/api/objc/RTCVideoTrack.mm
index 7422eff926ec44808dff11dc10ff1fb947ee2925..cb9f1a58234782de8b82473ee44772bedbd6d00e 100644
--- a/webrtc/api/objc/RTCVideoTrack.mm
+++ b/webrtc/api/objc/RTCVideoTrack.mm
@@ -33,12 +33,17 @@
   rtc::scoped_refptr<webrtc::VideoTrackInterface> track =
       factory.nativeFactory->CreateVideoTrack(nativeId,
                                               source.nativeVideoSource);
-  return [self initWithNativeTrack:track type:RTCMediaStreamTrackTypeVideo];
+  self = [super initWithNativeTrack:track type:RTCMediaStreamTrackTypeVideo];

[hjon_webrtc, 2016/02/19 20:55:34]

If |source| was actually an RTCAVFoundationVideoSource, calling self resulted in
|_source| becoming an RTCVideoSource instead. In turn, that caused the video
preview in AppRTCDemo to not appear because of this line:
https://code.google.com/p/chromium/codesearch#chromium/src/third_party/webrtc....

For the time being, I was concentrating on getting AppRTCDemo working, so there
might be a better way to fix this that I haven't seen yet.

[tkchin_webrtc, 2016/02/19 23:26:38]

you don't need to re-init the adapters, that should already be there.

to avoid the double source assign/init, lazily load the source in the getter for
the initWithNative case, and then assign source directly for the initWithFactory
case like you already have it.

- (RTCVideoSource *)source {
  if (!_source) {
    _source = ...<stuff from other ctor>
  }
  return _source;
}

[hjon_webrtc, 2016/02/19 23:58:36]

Done.

+  if (self) {
+    _adapters = [NSMutableArray array];
+    _source = source;
+  }
+  return self;
 }
 
-- (instancetype)initWithNativeMediaTrack:
+- (instancetype)initWithNativeTrack:
     (rtc::scoped_refptr<webrtc::MediaStreamTrackInterface>)nativeMediaTrack
-                                    type:(RTCMediaStreamTrackType)type {
+                               type:(RTCMediaStreamTrackType)type {
   NSParameterAssert(nativeMediaTrack);
   NSParameterAssert(type == RTCMediaStreamTrackTypeVideo);
   if (self = [super initWithNativeTrack:nativeMediaTrack type:type]) {