NTP/History: Remove comments referring to flexbox bug.

chrome/browser/resources/ntp4/new_tab.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 {
   /* It's necessary to put this here instead of in body in order to get the
      background-size of 100% to work properly */
   height: 100%;
   overflow: hidden;
 }
@@ skipping 428 matching lines @@
 }
 
 #footer .menu-container {
   -webkit-align-items: center;
   -webkit-flex-direction: row;
   -webkit-justify-content: flex-end;
   /* Put menus in a box so the order can easily be swapped. */
   display: -webkit-flex;
   height: 100%;
   margin: 0;
-  /* TODO(dubroy): Remove this if possible. According to the flexbox spec,
-     min-content is the default min-width for flex items. */
   min-width: -webkit-min-content;
 }
 
 #recently-closed-menu-button {
   -webkit-order: 1;
 }
 
 #other-sessions-menu-button {
   -webkit-order: 0;
 }
 
 .other-sessions-promo-message {
   display: none;
   padding: 0;
 }
 
 .other-sessions-promo-message:only-child {
   display: block;
 }
 
 .other-sessions-promo-message p {
   margin: 0;
 }