Fix an error in quick contact about document typeof

sharedComponents/quick-contact/quick-contact.component.ts

@@ -22,7 +22,7 @@ export class QuickContactComponent implements OnInit, OnDestroy {
   @ViewChild('drop') drop: ElementRef;
   
   ngOnInit() {
-    if (document !== undefined) {
+    if (typeof document !== 'undefined') {
       this.subscriptions.push(UIkit.util.on(document, 'beforehide', '#quick-contact', (event) => {
         if(this.sending) {
           event.preventDefault();