Exec `cancel` in background

src/ios/APPLocalNotification.m

@@ -59,19 +59,21 @@
  */
 - (void) cancel:(CDVInvokedUrlCommand*)command
 {
+    [self.commandDelegate runInBackground:^{
         NSArray* arguments       = [command arguments];
         NSString* notificationId = [arguments objectAtIndex:0];
         NSArray* notifications   = [[UIApplication sharedApplication] scheduledLocalNotifications];
 
-    for (UILocalNotification *notification in notifications)
+        for (UILocalNotification* notification in notifications)
         {
-        NSString *id = [notification.userInfo objectForKey:@"id"];
+            NSString* id = [notification.userInfo objectForKey:@"id"];
 
             if ([notificationId isEqualToString:id])
             {
                 [[UIApplication sharedApplication] cancelLocalNotification:notification];
             }
         }
+    }];
 }
 
 /**