Update voice interaction OOBE with new UX spec

chrome/browser/resources/chromeos/login/oobe_buttons.html

 <!-- Copyright 2016 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. -->
 
 <link rel="import" href="chrome://resources/polymer/v1_0/paper-styles/color.html">
 <link rel="import" href="chrome://resources/polymer/v1_0/iron-icon/iron-icon.html">
 <link rel="import" href="chrome://resources/polymer/v1_0/iron-iconset-svg/iron-iconset-svg.html">
 <link rel="import" href="chrome://resources/polymer/v1_0/paper-button/paper-button.html">
 
 <iron-iconset-svg name="oobe-buttons" size="24">
@@ skipping 36 matching lines @@
         --paper-button-flat-keyboard-focus: {
           border-color: var(--oobe-text-button-focused-border-color);
           border-radius: 2px;
           border-style: solid;
           border-width: 2px;
         };
       }
     </style>
     <paper-button id="textButton" on-tap="onClick_" disabled="[[disabled]]"
         inverse$="[[inverse]]" aria-label$="[[labelForAria]]"
-        border$="[[border]]">
+        border$="[[border]]" android$="[[android]]">
       <div id="container"
           class="flex layout horizontal center center-justified self-stretch">
         <content></content>
       </div>
     </paper-button>
   </template>
 </dom-module>
 
 <!--
   Material design square "<- Back" and "Next ->" buttons.
@@ skipping 55 matching lines @@
             class="flex layout horizontal center self-stretch">
           <hd-iron-icon icon1x="[[icon1x]]" icon2x="[[icon2x]]"
               class="oobe-icon">
           </hd-iron-icon>
           <content></content>
         </div>
       </div>
     </paper-button>
   </template>
 </dom-module>