Restore <img> src values now that grit converts these.

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 172 matching lines @@
   -webkit-box-align: center;
   display: -webkit-box;
   height: 49px;
 }
 
 #footer-content > * {
   margin: 0 9px;
 }
 
 #logo-img {
-  /* TODO(thakis): Remove once http://crbug.com/135179 is fixed */
-  content: url('chrome://theme/IDR_PRODUCT_LOGO');
   margin-top: 4px;
 }
 
 body.bare-minimum #footer {
   background: transparent;
   bottom: auto;
   font-weight: normal;
   position: absolute;
   right: 0;
 }
@@ skipping 241 matching lines @@
   padding: 0;
 }
 
 .other-sessions-promo-message:only-child {
   display: block;
 }
 
 .other-sessions-promo-message p {
   margin: 0;
 }