[MD Settings] Add a menu option to clear a cached credit card.

chrome/browser/resources/settings/passwords_and_forms_page/autofill_section.html

 <link rel="import" href="chrome://resources/cr_elements/cr_shared_menu/cr_shared_menu.html">
 <link rel="import" href="chrome://resources/html/action_link.html">
 <link rel="import" href="chrome://resources/html/polymer.html">
 <link rel="import" href="chrome://resources/polymer/v1_0/iron-list/iron-list.html">
 <link rel="import" href="chrome://resources/polymer/v1_0/paper-icon-button/paper-icon-button.html">
 <link rel="import" href="/passwords_and_forms_page/credit_card_edit_dialog.html">
 <link rel="import" href="/passwords_and_forms_page/passwords_shared_css.html">
 <link rel="import" href="/settings_shared_css.html">
 
 <dom-module id="settings-autofill-section">
@@ skipping 89 matching lines @@
         <a is="action-link" on-tap="onAddCreditCardTap_">
           $i18n{addCreditCard}
         </a>
       </div>
     </div>
     <cr-shared-menu id="creditCardSharedMenu">
       <div id="menuEditCreditCard" class="list-item menu-item"
           on-tap="onMenuEditCreditCardTap_">$i18n{editCreditCard}</div>
       <div id="menuRemoveCreditCard" class="list-item menu-item"
           on-tap="onMenuRemoveCreditCardTap_">$i18n{removeCreditCard}</div>
+      <div id="menuClearCreditCard" class="list-item menu-item"
+          on-tap="onMenuClearCreditCardTap_">$i18n{clearCreditCard}</div>
     </cr-shared-menu>
     <settings-credit-card-edit-dialog id="editCreditCardDialog">
     </settings-credit-card-edit-dialog>
   </template>
   <link rel="import" type="css" href="chrome://resources/css/action_link.css">
   <script src="/passwords_and_forms_page/autofill_section.js"></script>
 </dom-module>