Remove extra space in open dialog.

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 {
   height: 100%;
 }
 
 html.col-resize * {
   cursor: col-resize !important;
@@ skipping 282 matching lines @@
 
 /* Breadcrumbs and things under the title but above the list view. */
 .dialog-header {
   -webkit-box-align: center;
   -webkit-box-orient: horizontal;
   -webkit-transition: all 180ms ease;
   display: -webkit-box;
   margin: 7px 7px 7px 0;
 }
 
-[maximized] .dialog-header {
-  -webkit-padding-end: 70px;
+body[maximized][type='full-page'] .dialog-header {
+  -webkit-padding-end: 75px;
 }
 
 /* Container for the detail and thumbnail list views. */
 .dialog-body {
   -webkit-box-flex: 1;
   -webkit-box-orient: vertical;
   -webkit-transition: all 180ms ease;
   border-top: 1px solid #d4d4d4;
   display: -webkit-box;
   overflow: hidden;
@@ skipping 1140 matching lines @@
   opacity: 0.75;
   position: absolute;
   right: 0;
   top: 0;
 }
 
 #gear-button:hover::before {
   opacity: 1;
 }
 
-
 #gear-button {
   overflow: hidden;
   text-align: left;
   width: 54px;
 }
 
 #gear-button span.disclosureindicator {
   float: none;
   margin-left: 42px;
 }
@@ skipping 150 matching lines @@
 
 #default-action-dialog {
   min-width: 300px;
   width: auto;
 }
 
 .drive-welcome-wrapper {
   /* drive_welcome.css will override it once loaded. */
   display: none;
 }