Fix missing event param in isTargetClicked

Otherwise the global window.event property is used, and it might not
correspond to the value we want.

src/components/confirmpopup/ConfirmPopup.vue

@@ -176,7 +176,7 @@ export default {
                 this.resizeListener = null;
             }
         },
-        isTargetClicked() {
+        isTargetClicked(event) {
             return this.target && (this.target === event.target || this.target.contains(event.target));
         },
         containerRef(el) {

src/components/menu/Menu.vue

@@ -188,7 +188,7 @@ export default {
                 this.resizeListener = null;
             }
         },
-        isTargetClicked() {
+        isTargetClicked(event) {
             return this.target && (this.target === event.target || this.target.contains(event.target));
         },
         visible(item) {

src/components/tieredmenu/TieredMenu.vue

@@ -160,7 +160,7 @@ export default {
                 this.resizeListener = null;
             }
         },
-        isTargetClicked() {
+        isTargetClicked(event) {
             return this.target && (this.target === event.target || this.target.contains(event.target));
         },
         onLeafClick() {