Always call registerForRemoteNotifications from the main thread

Author: emawby

iOS_SDK/OneSignalSDK/Source/OneSignal.m

@@ -947,7 +947,9 @@ + (BOOL)registerForAPNsToken {
     [OneSignal onesignal_Log:ONE_S_LL_VERBOSE message:@"Firing registerForRemoteNotifications"];
 
     waitingForApnsResponse = true;
-    [[UIApplication sharedApplication] registerForRemoteNotifications];
+    [OneSignalHelper dispatch_async_on_main_queue:^{
+        [[UIApplication sharedApplication] registerForRemoteNotifications];
+    }];
 
     return true;
 }