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

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

Index: chrome/browser/resources/settings/passwords_and_forms_page/autofill_section.js
diff --git a/chrome/browser/resources/settings/passwords_and_forms_page/autofill_section.js b/chrome/browser/resources/settings/passwords_and_forms_page/autofill_section.js
index 4807235331338b639f5131c48160fe078a2fcec7..001cc0dd2c4fe74f5985d4161e0b3d8c9543f83e 100644
--- a/chrome/browser/resources/settings/passwords_and_forms_page/autofill_section.js
+++ b/chrome/browser/resources/settings/passwords_and_forms_page/autofill_section.js
@@ -119,6 +119,7 @@
       var creditCard = /** @type {!chrome.autofillPrivate.CreditCardEntry} */(
           menuEvent.model.item);
       this.$.menuRemoveCreditCard.hidden = !creditCard.metadata.isLocal;
+      this.$.menuClearCreditCard.hidden = !creditCard.metadata.isCached;
       this.$.creditCardSharedMenu.toggleMenu(
           Polymer.dom(e).localTarget, creditCard);
       e.stopPropagation();  // Prevent the tap event from closing the menu.
@@ -168,6 +169,16 @@
     },
 
     /**
+     * Handles tapping on the "Clear copy" button for cached credit cards.
+     * @private
+     */
+    onMenuClearCreditCardTap_: function() {
+      var menu = this.$.creditCardSharedMenu;
+      this.fire('clear-credit-card', menu.itemData);
+      menu.closeMenu();
+    },
+
+    /**
      * Closes the overflow menus.
      * @private
      */