MD Settings: About page, add an explicit 'aboutPageReady' signal.

chrome/browser/resources/settings/about_page/about_page_browser_proxy.js

Index: chrome/browser/resources/settings/about_page/about_page_browser_proxy.js
diff --git a/chrome/browser/resources/settings/about_page/about_page_browser_proxy.js b/chrome/browser/resources/settings/about_page/about_page_browser_proxy.js
index ace48ae3ad22ba7d19cad68e7ff4d31687ebd2ff..491eddeb8bec8a5062ed583a0c89b2004a5f0845 100644
--- a/chrome/browser/resources/settings/about_page/about_page_browser_proxy.js
+++ b/chrome/browser/resources/settings/about_page/about_page_browser_proxy.js
@@ -42,7 +42,12 @@ cr.define('settings', function() {
 
   AboutPageBrowserProxy.prototype = {
     /**
-     * Called once the page is ready. It results in one or more
+     * Indicates to the browser that the page is ready.
+     */
+    pageReady: function() {},
+
+    /**
+     * Request update status from the browser. It results in one or more
      * 'update-status-changed' WebUI events.
      */
     refreshUpdateStatus: function() {},
@@ -97,6 +102,11 @@ cr.define('settings', function() {
 
   AboutPageBrowserProxyImpl.prototype = {
     /** @override */
+    pageReady: function() {
+      chrome.send('aboutPageReady');
+    },
+
+    /** @override */
     refreshUpdateStatus: function() {
       chrome.send('refreshUpdateStatus');
     },