FIX: Add missing Object.entries polyfill for IE11

This was omitted when IE polyfills were migrated from polyfills.js to ie.js

plugins/discourse-internet-explorer/public/js/ie.js

@@ -1,6 +1,19 @@
 /* eslint-disable */
 
 // https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/entries
+if (!Object.entries) {
+  Object.entries = function(obj) {
+    var ownProps = Object.keys(obj),
+      i = ownProps.length,
+      resArray = new Array(i); // preallocate the Array
+    while (i--) resArray[i] = [ownProps[i], obj[ownProps[i]]];
+
+    return resArray;
+  };
+}
+
+// adapted from https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/entries
+// missing in ie only
 if (!Object.values) {
   Object.values = function(obj) {
     var ownProps = Object.keys(obj),