add findClosestAncestor

Function to find the closest ancestor of an element that matches the selection criterion

ui/media/js/utils.js

@@ -20,6 +20,19 @@ function getNextSibling(elem, selector) {
     }
 }
 
+function findClosestAncestor(element, selector) {
+  if (!element || !element.parentNode) {
+      // reached the top of the DOM tree, return null
+      return null;
+  } else if (element.parentNode.matches(selector)) {
+      // found an ancestor that matches the selector, return it
+      return element.parentNode;
+  } else {
+      // continue searching upwards
+      return findClosestAncestor(element.parentNode, selector);
+  }
+}
+
 
 /* Panel Stuff */