ntp: fix trash text color on dark themes with light text

chrome/browser/resources/ntp4/new_tab.css

 /* 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.
  */
 
 html {
   font-family: segoe ui, arial, helvetica, sans-serif;
   font-size: 14px;
   /* It's necessary to put this here instead of in body in order to get the
      background-size of 100% to work properly */
@@ skipping 222 matching lines @@
   -webkit-box-flex: 1;
 }
 
 #login-status-dismiss {
   min-width: 6em;
 }
 
 /* Trash. *********************************************************************/
 
 #trash {
+  color: #7F7F7F;
   height: 100%;
   position: absolute;
   opacity: 0;
   right: 0;
   top: 50px;
   -webkit-transition: top 200ms, opacity 0;
   -webkit-transition-delay: 0, 200ms;
 }
 
 #footer.showing-trash-mode #trash {
@@ skipping 28 matching lines @@
   padding: 0;
   position: absolute;
   margin: 0;
   max-width: 150px;
   min-width: 90px;
   outline: none;
   top: 0;
   z-index: 5;
   -webkit-transition: width 150ms, right 150ms, background-color 150ms;
 }