fix(test): new test wasn't working on some browsers

test/vaadin-combo-box-light.html

@@ -210,15 +210,21 @@
           if (rect.width === 0 || rect.height === 0) {
             return;
           }
-          const x = Math.round(rect.x);
-          const y = Math.round(rect.y);
+          const x = Math.ceil(rect.x);
+          const y = Math.ceil(rect.y);
           // Get the element which would be targeted, when the user
           // tries to click on this position
-          const target = elementFromPointDeep(x, y, elem.ownerDocument);
+          let target = elementFromPointDeep(x, y, elem.ownerDocument);
           if (!target) {
             return;
           }
 
+          // Check if the found element contains a slot (needed for other browsers than Chrome)
+          const slot = target.querySelector('slot');
+          if (slot && slot.assignedNodes({flatten: true}).indexOf(elem) !== -1) {
+            target = elem;
+          }
+
           fire('click', target);
         }