Don't show the apps page on the NTP if the app launcher is installed.

chrome/browser/resources/ntp4/new_tab.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.
 
 /**
  * @fileoverview New tab page
  * This is the main code for the new tab page used by touch-enabled Chrome
  * browsers.  For now this is still a prototype.
  */
 
@@ skipping 92 matching lines @@
 
     /** @override */
     appendTilePage: function(page, title, titleIsEditable, opt_refNode) {
       ntp.PageListView.prototype.appendTilePage.apply(this, arguments);
 
       if (promoBubble)
         window.setTimeout(promoBubble.reposition.bind(promoBubble), 0);
     }
   };
 
+  function gotShouldShowApps(shouldShowApps) {
+    if (shouldShowApps != loadTimeData.getBoolean('showApps')) {
+      // TODO(jeremya): update the UI in-place instead of reloading.
+      window.location.reload();
+      return;
+    }
+  }
+
   /**
    * Invoked at startup once the DOM is available to initialize the app.
    */
   function onLoad() {
+    // This will end up calling ntp.gotShouldShowApps.
+    chrome.send('getShouldShowApps');
     sectionsToWaitFor = loadTimeData.getBoolean('showApps') ? 2 : 1;
     if (loadTimeData.getBoolean('isDiscoveryInNTPEnabled'))
       sectionsToWaitFor++;
     measureNavDots();
 
     // Load the current theme colors.
     themeChanged();
 
     newTabView = new NewTabView();
 
@@ skipping 494 matching lines @@
   return {
     appAdded: appAdded,
     appMoved: appMoved,
     appRemoved: appRemoved,
     appsPrefChangeCallback: appsPrefChangeCallback,
     enterRearrangeMode: enterRearrangeMode,
     getAppsCallback: getAppsCallback,
     getAppsPageIndex: getAppsPageIndex,
     getCardSlider: getCardSlider,
     onLoad: onLoad,
+    gotShouldShowApps: gotShouldShowApps,
     leaveRearrangeMode: leaveRearrangeMode,
     logTimeToClick: logTimeToClick,
     NtpFollowAction: NtpFollowAction,
     saveAppPageName: saveAppPageName,
     setAppToBeHighlighted: setAppToBeHighlighted,
     setBookmarkBarAttached: setBookmarkBarAttached,
     setForeignSessions: setForeignSessions,
     setMostVisitedPages: setMostVisitedPages,
     setSuggestionsPages: setSuggestionsPages,
     setRecentlyClosedTabs: setRecentlyClosedTabs,
     setFaviconDominantColor: setFaviconDominantColor,
     showNotification: showNotification,
     themeChanged: themeChanged,
     updateLogin: updateLogin
   };
 });
 
 document.addEventListener('DOMContentLoaded', ntp.onLoad);
 
 var toCssPx = cr.ui.toCssPx;