Closure fix; force cast from Element to Node.

diff --git a/dygraph-utils.js b/dygraph-utils.js
index 11a2fba..f53c81e 100644 (file)
--- a/dygraph-utils.js
+++ b/dygraph-utils.js
@@ -1246,10 +1246,11 @@ Dygraph.isElementContainedBy = function(containee, container) {
   if (container === null || containee === null) {
     return false;
   }
-  while (containee && containee !== container) {
-    containee = containee.parentNode;
+  var containeeNode = /** @type {Node} */ (containee);
+  while (containeeNode && containeeNode !== container) {
+    containeeNode = containeeNode.parentNode;
   }
-  return (containee === container);
+  return (containeeNode === container);
 };