[MD settings] add getSiteDetails to site settings browser proxy

chrome/browser/resources/settings/site_settings/site_details.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
  * 'site-details' show the details (permissions and usage) for a given origin
  * under Site Settings.
  */
 Polymer({
   is: 'site-details',
 
-  behaviors: [SiteSettingsBehavior],
+  behaviors: [SiteSettingsBehavior, settings.RouteObserverBehavior],
 
   properties: {
     /**
      * The site that this widget is showing details for.
      * @type {SiteException}
      */
     site: {
       type: Object,
       observer: 'onSiteChanged_',
     },
@@ skipping 14 matching lines @@
 
   listeners: {
     'usage-deleted': 'onUsageDeleted',
   },
 
   ready: function() {
     this.ContentSettingsTypes = settings.ContentSettingsTypes;
   },
 
   /**
+   * settings.RouteObserverBehavior
+   * @param {!settings.Route} route
+   * @protected
+   */
+  currentRouteChanged: function(route) {
+    var site = settings.getQueryParameters().get('site');
+    if (!site)
+      return;
+    this.browserProxy.getSiteDetails(site).then(function(siteInfo) {
+      this.site = siteInfo;
+      // TODO(dschuyler): set originForDisplay for fetchUsageTotal.
+      // TODO(dschuyler): set the page title to originForDisplay.
+    }.bind(this));
+  },
+
+  /**
    * Handler for when the origin changes.
    */
   onSiteChanged_: function() {
-    // Using originForDisplay avoids the [*.] prefix that some exceptions use.
-    var url = new URL(this.ensureUrlHasScheme(this.site.originForDisplay));
-    this.$.usageApi.fetchUsageTotal(url.hostname);
+    // originForDisplay may be initially undefined if the user follows a direct
+    // link (URL) to this page.
+    if (this.site.originForDisplay !== undefined) {
+      // Using originForDisplay avoids the [*.] prefix that some exceptions use.
+      var url = new URL(this.ensureUrlHasScheme(this.site.originForDisplay));
+      this.$.usageApi.fetchUsageTotal(url.hostname);
+    }
   },
 
   /**
    * Clears all data stored for the current origin.
    */
   onClearStorage_: function() {
     this.$.usageApi.clearUsage(this.site.origin, this.storageType_);
   },
 
   /**
@@ skipping 30 matching lines @@
 
   /**
    * Returns true if one or more permission is showing.
    */
   permissionShowing_: function() {
     return Array.prototype.some.call(
         this.root.querySelectorAll('site-details-permission'),
         function(element) { return element.offsetHeight > 0; });
   },
 });