[ntp] fix font measuring hack

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 {
-  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 */
   height: 100%;
   overflow: hidden;
 }
 
 body {
   /* Don't highlight links when they're tapped. Safari has bugs here that
      show up as flicker when dragging in some situations */
@@ skipping 284 matching lines @@
 #footer.showing-trash-mode #trash.drag-target .lid {
   -webkit-transform: rotate(-45deg);
 }
 
 html[dir='rtl'] #footer.showing-trash-mode #trash.drag-target .lid {
   -webkit-transform: rotate(45deg);
 }
 
 #fontMeasuringDiv {
   /* The font attributes match the nav inputs. */
+  font: -webkit-small-control;
   font-size: 8pt;
   font-weight: bold;
   pointer-events: none;
   position: absolute;
   visibility: hidden;
 }
 
 /* Page switcher buttons. *****************************************************/
 
 .page-switcher {
@@ skipping 48 matching lines @@
 
 /* Reserve space for the menu button even when it's hidden. */
 #footer.showing-trash-mode #chrome-web-store-href {
   visibility: hidden;
 }
 
 #footer.showing-trash-mode #chrome-web-store-href {
   -webkit-transition-delay: 0;
   opacity: 0;
 }