[MD settings] padding at the bottom of sub-pages

chrome/browser/resources/settings/settings_page/settings_subpage.html

 <link rel="import" href="chrome://resources/html/polymer.html">
 <link rel="import" href="chrome://resources/polymer/v1_0/iron-resizable-behavior/iron-resizable-behavior.html">
 <link rel="import" href="chrome://resources/polymer/v1_0/neon-animation/neon-animatable-behavior.html">
 <link rel="import" href="chrome://resources/polymer/v1_0/paper-icon-button/paper-icon-button.html">
 <link rel="import" href="/icons.html">
 <link rel="import" href="/route.html">
 <link rel="import" href="/settings_page/settings_subpage_search.html">
 <link rel="import" href="/settings_shared_css.html">
 
 <dom-module id="settings-subpage">
   <template>
     <style include="settings-shared">
       :host {
         --iron-icon-fill-color: var(--settings-nav-grey);
         display: block;
+        padding-bottom: 60px;
       }
 
       .settings-box.first {
         min-height: 40px;
         padding-top: 8px;
       }
 
       paper-icon-button {
         /* The inner icon is 20px in size. paper-icon-button has 8px padding. */
         height: 36px;
@@ skipping 19 matching lines @@
       <template is="dom-if" if="[[searchLabel]]">
         <settings-subpage-search label="[[searchLabel]]"
             on-search-changed="onSearchChanged_">
         </settings-subpage-search>
       </template>
     </div>
     <content></content>
   </template>
   <script src="settings_subpage.js"></script>
 </dom-module>