[MD Bookmarks] Fix sidebar issues.

ui/webui/resources/js/cr/ui/splitter.js

 // Copyright (c) 2012 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.
 
 /**
  * @fileoverview This implements a splitter element which can be used to resize
  * elements in split panes.
  *
  * The parent of the splitter should be an hbox (display: -webkit-box) with at
  * least one previous element sibling. The splitter controls the width of the
@@ skipping 231 matching lines @@
 
     /**
      * Handles splitter moves. Updates width of the element being resized.
      * @param {number} deltaX The change of splitter horizontal position.
      * @protected
      */
     handleSplitterDragMove: function(deltaX) {
       var targetElement = this.getResizeTarget_();
       var newWidth = this.startWidth_ + this.calcDeltaX_(deltaX);
       targetElement.style.width = newWidth + 'px';
+      cr.dispatchSimpleEvent(this, 'dragmove');
     },
 
     /**
      * Handles end of the splitter dragging. This fires a 'resize' event if the
      * size changed.
      * @protected
      */
     handleSplitterDragEnd: function() {
       // Check if the size changed.
       var targetElement = this.getResizeTarget_();
       var doc = targetElement.ownerDocument;
       var computedWidth =
           parseFloat(doc.defaultView.getComputedStyle(targetElement).width);
       if (this.startWidth_ != computedWidth)
         cr.dispatchSimpleEvent(this, 'resize');
     },
   };
 
   return {Splitter: Splitter};
 });