MD Settings: Certificate manager, remove border from last certificate entry.

chrome/browser/resources/settings/certificate_manager_page/certificate_subentry.html

 <link rel="import" href="chrome://resources/html/polymer.html">
 <link rel="import" href="chrome://md-settings/certificate_manager_page/certificates_browser_proxy.html">
 <link rel="import" href="chrome://resources/cr_elements/cr_expand_button/cr_expand_button.html">
 <link rel="import" href="chrome://resources/polymer/v1_0/iron-dropdown/iron-dropdown.html">
 <link rel="import" href="chrome://resources/polymer/v1_0/iron-icons/iron-icons.html">
 <link rel="import" href="chrome://resources/polymer/v1_0/paper-icon-button/paper-icon-button.html">
 <link rel="import" href="chrome://resources/polymer/v1_0/paper-item/paper-item.html">
 <link rel="import" href="chrome://md-settings/settings_shared_css.html">
 
 <dom-module id="settings-certificate-subentry">
@@ skipping 13 matching lines @@
       .untrusted {
         color: var(--settings-error-color);
         font-weight: 500;
         text-transform: uppercase;
         -webkit-margin-end: 16px;
       }
 
       paper-item:hover {
         background-color: var(--settings-hover-color);
       }
+
+      :host([is-last]) .list-item {
+        border-bottom: none;
+      }
     </style>
     <div class="list-item underbar">
       <div class="untrusted" hidden$="[[!model.untrusted]]">
         $i18n{certificateManagerUntrusted}
       </div>
       <div class="name">[[model.name]]</div>
       <paper-icon-button id="dots" icon="more-vert" toggles
           active="{{menuOpened}}"></paper-icon-button>
       <!-- TODO(dpapad): Figure out RTL for this menu -->
       <template is="dom-if" if="[[menuOpened]]">
@@ skipping 14 matching lines @@
                 on-tap="onDeleteTap_">
               $i18n{certificateManagerDelete}
             </paper-item>
           </div>
         </iron-dropdown>
       </template>
     <div>
   </template>
   <script src="certificate_subentry.js"></script>
 </dom-module>