Files.app: Removed the column divider at the next to the checkbox.

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 1594 matching lines @@
     url('../images/files/ui/new-ui/vertical_separator.png') 1x,
     url('../images/files/ui/new-ui/2x/vertical_separator.png') 2x);
   background-position: center;
   background-repeat: repeat-y;
   border: none;
   height: 20px;
   top: 10px;
   width: 5px;
 }
 
+body[new-ui] .table-header-splitter:last-child {
+  display: none;
+}
+
 /* Container for a table header. */
 .table-header {
   background-color: #f5f5f5;
   border-bottom: 1px #d2d2d2 solid;
   box-sizing: border-box;
   height: 27px;
 }
 
 body[new-ui] .table-header {
   background-color: transparent;
@@ skipping 800 matching lines @@
 body[new-ui] #iframe-drag-area {
   -webkit-app-region: drag;
   height: 45px;
   left: 64px;
   position: absolute;
   right: 70px;
   top: 0;
   width: auto;
   z-index: 101;
 }