Fixed non-smooth animation of gdata-settings button.

chrome/browser/resources/file_manager/css/file_manager.css

 /* 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. */
 
 html.col-resize * {
   cursor: col-resize !important;
 }
 
 /* Outer frame of the dialog. */
 body {
@@ skipping 1167 matching lines @@
 body[ash] .dialog-title,
 body[type='full-page'] [invisibleif='full-page'],
 body:not([type='full-page']) [visibleif='full-page'],
 body:not([type='saveas-file']) [visibleif='saveas-file'],
 body:not([type='saveas-file']):not([type='full-page'])
     [visibleif='saveas-file full-page'] {
   display: none;
 }
 
 #gdata-settings {
+  overflow: hidden;
   text-align: left;
+  width: 54px;
 }
 
 #gdata-settings img {
   margin-left: 12px;
 }
 
 #gdata-settings span.disclosureindicator {
   float: none;
   margin-left: 1px;
 }
@@ skipping 91 matching lines @@
   left: 0;
   padding: 10px;
   position: absolute;
   right: 0;
   top: 28px;  /* Leave room for the file list header. */
 }
 
 .dialog-container:not([gdrive-welcome='page']) #no-search-results[show] {
   display: block;
 }