Fix apps page footer shrinking/overlap for small window sizes.

chrome/browser/resources/ntp4/nav_dot.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. */
 
 /* TODO(estade): handle overflow better? I tried overflow-x: hidden and
    overflow-y: visible (for the new dot animation), but this makes a scroll
    bar appear */
 #dot-list {
   /* Expand to take up all available horizontal space.  */
   -webkit-box-flex: 1;
   /* Center child dots. */
   -webkit-box-pack: center;
-  display: -webkit-box;
+  display: -webkit-flex;
   height: 100%;
   list-style-type: none;
   margin: 0;
   padding: 0;
 }
 
 html.starting-up #dot-list {
   display: none;
 }
 
 .dot {
-  -webkit-box-flex: 1;
   -webkit-margin-end: 10px;
   -webkit-padding-start: 2px;
   -webkit-transition: -webkit-margin-end 250ms, max-width 250ms, opacity 250ms;
   box-sizing: border-box;
   cursor: pointer;
   /* max-width: Set in new_tab.js. See measureNavDots() */
   outline: none;
   text-align: left;
 }
 
@@ skipping 51 matching lines @@
 
 .dot:focus .selection-bar,
 .dot:hover .selection-bar,
 .dot.drag-target .selection-bar {
   border-color: #b2b2b2;
 }
 
 .dot.selected .selection-bar {
   border-color: #7f7f7f;
 }