[uber] Redoing the homepage selection UI

chrome/browser/resources/options2/pref_ui.js

 // Copyright (c) 2012 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.
 
 // TODO(jhawkins): Add dialog-pref support to all preference controls.
 
 cr.define('options', function() {
 
   var Preferences = options.Preferences;
 
@@ skipping 593 matching lines @@
   /////////////////////////////////////////////////////////////////////////////
   // PrefTextField class:
 
   // Define a constructor that uses an input element as its underlying element.
   var PrefTextField = cr.ui.define('input');
 
   PrefTextField.prototype = {
     // Set up the prototype chain
     __proto__: HTMLInputElement.prototype,
 
+    prefValue_: null,
+
+    savePrefState: function() {
+      switch(this.dataType) {
+        case 'number':
+          Preferences.setIntegerPref(this.pref, this.value, this.metric);
+          break;
+        case 'double':
+          Preferences.setDoublePref(this.pref, this.value, this.metric);
+          break;
+        case 'url':
+          Preferences.setURLPref(this.pref, this.value, this.metric);
+          break;
+        default:
+          Preferences.setStringPref(this.pref, this.value, this.metric);
+          break;
+      }
+    },
+
+    resetPrefState: function() {
+      this.value = this.prefValue_;
+    },
+
     /**
      * Initialization function for the cr.ui framework.
      */
     decorate: function() {
       var self = this;
 
       // Listen to pref changes.
       Preferences.getInstance().addEventListener(this.pref,
           function(event) {
             self.value = event.value && event.value['value'] != undefined ?
                 event.value['value'] : event.value;
 
             updateElementState_(self, event);
+
+            self.prefValue_ = self.value;
           });
 
       // Listen to user events.
-      this.addEventListener('change',
-          function(e) {
-            switch(self.dataType) {
-              case 'number':
-                Preferences.setIntegerPref(self.pref, self.value, self.metric);
-                break;
-              case 'double':
-                Preferences.setDoublePref(self.pref, self.value, self.metric);
-                break;
-              case 'url':
-                Preferences.setURLPref(self.pref, self.value, self.metric);
-                break;
-              default:
-                Preferences.setStringPref(self.pref, self.value, self.metric);
-                break;
-            }
-          });
+      if (!self.dialogPref) {
+        this.addEventListener('change', function(e) {
+          self.savePrefState.bind(self);
+        });
+      }
 
       window.addEventListener('unload',
           function() {
             if (document.activeElement == self)
               self.blur();
           });
     },
 
     /**
      * See |updateDisabledState_| above.
@@ skipping 88 matching lines @@
     PrefNumber: PrefNumber,
     PrefNumeric: PrefNumeric,
     PrefRadio: PrefRadio,
     PrefRange: PrefRange,
     PrefSelect: PrefSelect,
     PrefTextField: PrefTextField,
     PrefButton: PrefButton
   };
 
 });