MD Settings: Update some ChromeOS inputs to on-change

chrome/browser/resources/settings/printing_page/cups_add_printer_dialog_util.js

 // 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.
 
 /** 'add-printers-list' is the list of discovered printers. */
 Polymer({
   is: 'add-printer-list',
 
   properties: {
     /** @type {!Array<!CupsPrinterInfo>} */
@@ skipping 68 matching lines @@
     this.$$('iron-dropdown').close();
     this.$.searchIcon.hidden = true;
     this.$.dropdownIcon.hidden = false;
 
     this.selectedItem = event.model.item;
     this.searchTerm_ = '';
     this.$$('input').value = this.selectedItem;
   },
 
   /** @private */
-  onBlur_: function() {
+  onChange_: function() {
     this.$.searchIcon.hidden = true;
     this.$.dropdownIcon.hidden = false;
   },
 
   /** @private */
   filterItems_: function(searchTerm) {
     if (!searchTerm)
       return null;
     return function(item) {
       return item.toLowerCase().includes(searchTerm.toLowerCase());
     };
   },
 });
 
 /** 'add-printer-dialog' is the template of the Add Printer dialog. */
 Polymer({
   is: 'add-printer-dialog',
 
   /** @private */
   attached: function() {
     this.$.dialog.showModal();
   },
 
   close: function() {
     this.$.dialog.close();
   },
 });