[filebrowser] Support renaming in Gallery.

chrome/browser/resources/file_manager/js/image_editor/image_util.js

 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 
 // Namespace object for the utilities.
 function ImageUtil() {}
 
 // Performance trace.
 ImageUtil.trace = (function() {
@@ skipping 416 matching lines @@
     callback(context.canvas);
   } else {
     var self = this;
     this.timeout_ = setTimeout(
         function() {
           self.timeout_ = null;
           self.copyStrip_(context, lastRow, rowCount);
         }, 0);
   }
 };
+
+ImageUtil.getFullNameFromUrl = function(url) {
+  if (url.indexOf('/') != -1)
+    return url.substr(url.lastIndexOf('/') + 1);
+  else
+    return url;
+};
+
+ImageUtil.getFileNameFromFullName = function(name) {
+  var index = name.lastIndexOf('.');
+  if (index != -1)
+    return name.substr(0, index);
+  else
+    return name;
+};
+
+ImageUtil.getFileNameFromUrl = function(url) {
+  return ImageUtil.getFileNameFromFullName(ImageUtil.getFullNameFromUrl(url));
+};
+
+ImageUtil.replaceFileNameInFullName = function(fullName, name) {
+  var index = fullName.lastIndexOf('.');
+  if (index != -1)
+    return name + fullName.substr(index);
+  else
+    return name;
+};