WebUI cr-search-field: Trigger event after programmatically clearing query.

chrome/test/data/webui/cr_elements/cr_toolbar_search_field_tests.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.
 
 /** @fileoverview Suite of tests for cr-toolbar-search-field. */
 cr.define('cr_toolbar_search_field', function() {
   function registerTests() {
     suite('cr-toolbar-search-field', function() {
       /** @type {?CrToolbarSearchFieldElement} */
       var field = null;
@@ skipping 56 matching lines @@
         assertFalse(field.showingSearch);
         assertEquals('', field.getValue());
 
         simulateSearch('query2');
         // Expecting identical query to be ignored.
         simulateSearch('query2');
 
         assertEquals(['query1', '', 'query2'].join(), searches.join());
       });
 
+      test('notifies on setValue', function() {
+        MockInteractions.tap(field);
+        field.setValue('foo');
+        field.setValue('');
+        field.setValue('bar');
+        // Expecting identical query to be ignored.
+        field.setValue('bar');
+        field.setValue('baz');
+        assertEquals(['foo', '', 'bar', 'baz'].join(), searches.join());
+      });
+
       test('blur does not close field when a search is active', function() {
         MockInteractions.tap(field);
         simulateSearch('test');
         MockInteractions.blur(field.$.searchInput);
 
         assertTrue(field.showingSearch);
       });
     });
   }
 
   return {
     registerTests: registerTests,
   };
 });