Update iOS AppRTCDemo to use the updated Objective-C API.

webrtc/examples/objc/AppRTCDemo/tests/ARDAppClientTest.mm

Index: webrtc/examples/objc/AppRTCDemo/tests/ARDAppClientTest.mm
diff --git a/webrtc/examples/objc/AppRTCDemo/tests/ARDAppClientTest.mm b/webrtc/examples/objc/AppRTCDemo/tests/ARDAppClientTest.mm
index 2470e50c9ebd1bcaf4d30d3c60a5a49c6f11168c..6359431a79c7d1fbebedfac9909b2ff4a1eafb06 100644
--- a/webrtc/examples/objc/AppRTCDemo/tests/ARDAppClientTest.mm
+++ b/webrtc/examples/objc/AppRTCDemo/tests/ARDAppClientTest.mm
@@ -15,9 +15,9 @@
 #import "ARDJoinResponse+Internal.h"
 #import "ARDMessageResponse+Internal.h"
 #import "ARDSDPUtils.h"
-#import "RTCMediaConstraints.h"
-#import "RTCPeerConnectionFactory.h"
-#import "RTCSessionDescription.h"
+#import "webrtc/api/objc/RTCMediaConstraints.h"
+#import "webrtc/api/objc/RTCPeerConnectionFactory.h"
+#import "webrtc/api/objc/RTCSessionDescription.h"
 
 #include "webrtc/base/gunit.h"
 #include "webrtc/base/ssladapter.h"
@@ -301,7 +301,7 @@
   NSString *expectedSdp = @("m=video 9 RTP/SAVPF 120 100 116 117 96\n"
                             "a=rtpmap:120 H264/90000\n");
   RTCSessionDescription* desc =
-      [[RTCSessionDescription alloc] initWithType:@"offer" sdp:sdp];
+      [[RTCSessionDescription alloc] initWithType:RTCSdpTypeOffer sdp:sdp];
   RTCSessionDescription *h264Desc =
       [ARDSDPUtils descriptionForDescription:desc
                          preferredVideoCodec:@"H264"];