[MD settings] adding DefaultBrowser settings page

chrome/browser/resources/settings/default_browser_page/default_browser_page.js

+// Copyright 2015 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
+ * 'settings-default-browser-page' is the settings page that contains
+ * settings to change the default browser (i.e. which the OS will open).
+ *
+ * Example:
+ *
+ *   <iron-animated-pages>
+ *     <settings-default-browser-page>
+ *     </settings-default-browser-page>
+ *     ... other pages ...
+ *   </iron-animated-pages>
+ *
+ * @group Chrome Settings Elements
+ * @element settings-default-browser-page
+ */
+Polymer({
+  is: 'settings-default-browser-page',
+
+  properties: {
+    /**
+     * The current active route.
+     */
+    currentRoute: {
+      type: Object,
+      notify: true,
+    },
+
+    /**
+     * A message about whether Chrome is the default browser.
+     */
+    message_: {
+      type: String,
+    },
+
+    /**
+     * Show or hide an error indicator showing whether SetAsDefault succeeded.
+     */
+    showError_: {
+      type: Boolean,
+      value: false,
+    },
+
+    /**
+     * Only show the SetAsDefault button if we have permission to set it.
+     */
+    showButton_: {
+      type: Boolean,
+    },
+  },
+
+  behaviors: [
+    I18nBehavior,
+  ],
+
+  ready: function() {
+    var self = this;
+    cr.define('Settings', function() {
+      return {
+        setAsDefaultConcluded: function() {
+          return self.setAsDefaultConcluded_.apply(self, arguments);
+        },
+        updateDefaultBrowserState: function() {
+          return self.updateDefaultBrowserState_.apply(self, arguments);
+        },
+      };
+    });
+    chrome.send('SettingsDefaultBrowser.requestDefaultBrowserState');
+  },
+
+  /**
+   * @param {boolean} succeeded
+   * @private
+   */
+  setAsDefaultConcluded_: function(succeeded) {
+    this.showError_ = !succeeded;
+  },
+
+  /**
+   * @param {boolean} isDefault Whether Chrome is currently the user's default
+   *   browser.
+   * @param {boolean} canBeDefault Whether Chrome can be the default browser on
+   *   this system.
+   * @private
+   */
+  updateDefaultBrowserState_: function(isDefault, canBeDefault) {
+    this.showButton_ = !isDefault && canBeDefault;
+    if (canBeDefault) {
+      this.message_ = loadTimeData.getString(isDefault ?
+          'defaultBroswerDefault' :
+          'defaultBroswerNotDefault');
+    } else {
+      this.message_ = loadTimeData.getString('defaultBroswerUnknown');
+    }
+  },
+
+  /** @private */
+  onSetDefaultBrowserTap_: function() {
+    chrome.send('SettingsDefaultBrowser.setAsDefaultBrowser');
+  },
+});