Explicitly @synthesize ObjC @properties

This is required after https://code.google.com/p/gyp/source/detail?r=1768
turned on -Wobjc-missing-property-synthesis for ninja builds (until then it
was only enabled for xcode builds) to allow chromium_deps to roll in
webrtc/DEPS.

BUG=2560
R=kjellander@webrtc.org

Review URL: https://webrtc-codereview.appspot.com/3089004

git-svn-id: http://webrtc.googlecode.com/svn/trunk@5047 4adac7df-926f-26a2-2b94-8c16560cd09d
diff --git a/talk/examples/ios/AppRTCDemo/APPRTCAppDelegate.m b/talk/examples/ios/AppRTCDemo/APPRTCAppDelegate.m
index 34aa752..65cdd09 100644
--- a/talk/examples/ios/AppRTCDemo/APPRTCAppDelegate.m
+++ b/talk/examples/ios/AppRTCDemo/APPRTCAppDelegate.m
@@ -142,6 +142,14 @@
 
 @implementation APPRTCAppDelegate
 
+@synthesize window = _window;
+@synthesize viewController = _viewController;
+@synthesize client = _client;
+@synthesize pcObserver = _pcObserver;
+@synthesize peerConnection = _peerConnection;
+@synthesize peerConnectionFactory = _peerConnectionFactory;
+@synthesize queuedRemoteCandidates = _queuedRemoteCandidates;
+
 #pragma mark - UIApplicationDelegate methods
 
 - (BOOL)application:(UIApplication *)application