ChromeOS: Update styles of material design OOBE.

chrome/browser/resources/chromeos/login/oobe_dialog.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/iron-flex-layout/classes/iron-flex-layout.html">
 <link rel="import" href="chrome://resources/polymer/v1_0/paper-styles/color.html">
 
 <!--
-  Simple OOBE card which should be used for OOBE UI elements.
-  It has blue header and grey footer.
+  Simple OOBE dialog which should be used for OOBE UI elements.
+  It has correct size and padding. It can display top left icon, and has
+  three parts: header (which should have <h1>title</h1>), footer (content part),
+  and optional buttons container at the bottom.
 
   Example:
-    <oobe-dialog>
+    <link rel="stylesheet" href="oobe_dialog_parameters.css">
+    <oobe-dialog has-buttons>
       <iron-icon ... class="oobe-icon">
-      <div class="header flex vertical layout end-justified start">
+      <div class="header">
+        <h1> class="title">Title</h1>
+        <div class="subtitle">Subtitle</div>
+      </div>
+      <div class="footer">
         ...
       </div>
-      <oobe-input-form class="footer" ...>
-      </oobe-input-form>
-      <oobe-text-button class="footer" label="OK" ...>
-      </oobe-text-button>
+      <div class="bottom-buttons">
+        ...
+      </div>
     </oobe-dialog>
 
   Add class |header| to all which you want to go inside the header.  Similar
-  with clases |footer| and |oobe-icon|.
+  with clases |footer|, |bottom-buttons| and |oobe-icon|. |bottom-buttons| block
+  is shown only if |has-buttons| attribute is set.
 -->
 <dom-module name="oobe-dialog">
   <template>
     <link rel="stylesheet" href="oobe_dialog_host.css">
     <link rel="stylesheet" href="oobe_dialog.css">
     <div id="header-container">
       <div class="oobe-icon-div">
         <content select=".oobe-icon"></content>
       </div>
       <div class="oobe-header layout vertical">
         <content select=".header"></content>
       </div>
     </div>
     <div id="footer-container" class="flex">
       <content select=".footer"></content>
     </div>
     <template is="dom-if" if="[[hasButtons]]">
       <div id="oobe-bottom" class="layout horizontal center">
         <content select=".bottom-buttons"></content>
       </div>
     </template>
   </template>
 </dom-module>