Avoid Npe for call with a guest without name

11-02 03:45:20.115 27450 27450 D CallActivity: initGridAdapter
11-02 03:45:20.116 27450 27450 D CallActivity: removeParticipantDisplayItem
11-02 03:45:20.116 27450 27450 D CallActivity: removeParticipantDisplayItem
11-02 03:45:20.119 27450 27450 W MagicWebRTCUtils: No payload types with name H264
11-02 03:45:20.141 27450 27450 W System.err: java.lang.NullPointerException: Parameter specified as non-null is null: method com.nextcloud.talk.activities.CallActiv
ity$OfferAnswerNickProvider$WebRtcMessageListener.onOffer, parameter nick
11-02 03:45:20.141 27450 27450 W System.err:    at com.nextcloud.talk.activities.CallActivity$OfferAnswerNickProvider$WebRtcMessageListener.onOffer(Unknown Source:7
)
11-02 03:45:20.141 27450 27450 W System.err:    at com.nextcloud.talk.signaling.WebRtcMessageNotifier.notifyOffer(WebRtcMessageNotifier.java:99)
11-02 03:45:20.141 27450 27450 W System.err:    at com.nextcloud.talk.signaling.SignalingMessageReceiver.processSignalingMessage(SignalingMessageReceiver.java:746)
11-02 03:45:20.142 27450 27450 W System.err:    at com.nextcloud.talk.activities.CallActivity$InternalSignalingMessageReceiver.process(CallActivity.kt:2707)
11-02 03:45:20.142 27450 27450 W System.err:    at com.nextcloud.talk.activities.CallActivity.receivedSignalingMessage(CallActivity.kt:1889)
11-02 03:45:20.142 27450 27450 W System.err:    at com.nextcloud.talk.activities.CallActivity.receivedSignalingMessages(CallActivity.kt:1865)
11-02 03:45:20.142 27450 27450 W System.err:    at com.nextcloud.talk.activities.CallActivity.access$receivedSignalingMessages(CallActivity.kt:190)
11-02 03:45:20.142 27450 27450 W System.err:    at com.nextcloud.talk.activities.CallActivity$pullSignalingMessages$5.onNext(CallActivity.kt:1768)
11-02 03:45:20.142 27450 27450 W System.err:    at com.nextcloud.talk.activities.CallActivity$pullSignalingMessages$5.onNext(CallActivity.kt:1762)
11-02 03:45:20.142 27450 27450 W System.err:    at io.reactivex.internal.util.HalfSerializer.onNext(HalfSerializer.java:107)
11-02 03:45:20.143 27450 27450 W System.err:    at io.reactivex.internal.operators.observable.ObservableRetryWhen$RepeatWhenObserver.onNext(ObservableRetryWhen.java
:100)
11-02 03:45:20.143 27450 30048 W MagicWebRTCUtils: No payload types with name H264
11-02 03:45:20.143 27450 27450 W System.err:    at io.reactivex.internal.operators.observable.ObservableDoOnEach$DoOnEachObserver.onNext(ObservableDoOnEach.java:101
)
11-02 03:45:20.143 27450 27450 W System.err:    at io.reactivex.internal.operators.observable.ObservableTakeWhile$TakeWhileObserver.onNext(ObservableTakeWhile.java:
88)
11-02 03:45:20.143 27450 27450 W System.err:    at io.reactivex.internal.util.HalfSerializer.onNext(HalfSerializer.java:107)
11-02 03:45:20.143 27450 27450 W System.err:    at io.reactivex.internal.operators.observable.ObservableRepeatWhen$RepeatWhenObserver.onNext(ObservableRepeatWhen.ja
va:100)
11-02 03:45:20.143 27450 27450 W System.err:    at io.reactivex.internal.operators.observable.ObservableObserveOn$ObserveOnObserver.drainNormal(ObservableObserveOn.
java:201)
11-02 03:45:20.143 27450 27450 W System.err:    at io.reactivex.internal.operators.observable.ObservableObserveOn$ObserveOnObserver.run(ObservableObserveOn.java:255
)
11-02 03:45:20.144 27450 27450 W System.err:    at io.reactivex.android.schedulers.HandlerScheduler$ScheduledRunnable.run(HandlerScheduler.java:124)
11-02 03:45:20.144 27450 27450 W System.err:    at android.os.Handler.handleCallback(Handler.java:938)
11-02 03:45:20.144 27450 27450 W System.err:    at android.os.Handler.dispatchMessage(Handler.java:99)
11-02 03:45:20.144 27450 27450 W System.err:    at android.os.Looper.loop(Looper.java:223)
11-02 03:45:20.144 27450 27450 W System.err:    at android.app.ActivityThread.main(ActivityThread.java:7664)
11-02 03:45:20.144 27450 27450 W System.err:    at java.lang.reflect.Method.invoke(Native Method)
11-02 03:45:20.144 27450 27450 W System.err:    at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:592)
11-02 03:45:20.144 27450 27450 W System.err:    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:947)
11-02 03:45:20.145 27450 27450 E AndroidRuntime: FATAL EXCEPTION: main

Signed-off-by: Marcel Hibbe <[email protected]>

app/src/main/java/com/nextcloud/talk/activities/CallActivity.kt

@@ -2715,11 +2715,11 @@ class CallActivity : CallBaseActivity() {
             private set
 
         private inner class WebRtcMessageListener : SignalingMessageReceiver.WebRtcMessageListener {
-            override fun onOffer(sdp: String, nick: String) {
+            override fun onOffer(sdp: String, nick: String?) {
                 onOfferOrAnswer(nick)
             }
 
-            override fun onAnswer(sdp: String, nick: String) {
+            override fun onAnswer(sdp: String, nick: String?) {
                 onOfferOrAnswer(nick)
             }
 
@@ -2732,7 +2732,7 @@ class CallActivity : CallBaseActivity() {
             }
         }
 
-        private fun onOfferOrAnswer(nick: String) {
+        private fun onOfferOrAnswer(nick: String?) {
             this.nick = nick
             if (callParticipants[sessionId] != null) {
                 callParticipants[sessionId]!!.setNick(nick)