Add destroyEventHandlers()

Author: Eric-Guo

app/assets/javascripts/jquery-fileupload/jquery.fileupload.js

@@ -1080,6 +1080,8 @@
         _handleFileTreeEntry: function (entry, path) {
             var that = this,
                 dfd = $.Deferred(),
+                entries = [],
+                dirReader,
                 errorHandler = function (e) {
                     if (e && !e.entry) {
                         e.entry = entry;
@@ -1107,8 +1109,7 @@
                             readEntries();
                         }
                     }, errorHandler);
-                },
-                dirReader, entries = [];
+                };
             path = path || '';
             if (entry.isFile) {
                 if (entry._file) {
@@ -1311,6 +1312,10 @@
             this._off(this.options.fileInput, 'change');
         },
 
+        _destroy: function () {
+            this._destroyEventHandlers();
+        },
+
         _setOption: function (key, value) {
             var reinit = $.inArray(key, this._specialOptions) !== -1;
             if (reinit) {