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

chrome/browser/ui/webui/ntp/new_tab_page_handler.cc

 // 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.
 
 #include "chrome/browser/ui/webui/ntp/new_tab_page_handler.h"
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/metrics/histogram.h"
+#include "chrome/browser/extensions/app_launcher.h"
 #include "chrome/browser/prefs/pref_service.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/sync/profile_sync_service.h"
 #include "chrome/browser/ui/webui/ntp/new_tab_ui.h"
 #include "chrome/browser/web_resource/notification_promo.h"
 #include "chrome/common/pref_names.h"
 #include "content/public/browser/notification_service.h"
 #include "content/public/browser/web_ui.h"
 #include "grit/chromium_strings.h"
 #include "grit/generated_resources.h"
@@ skipping 45 matching lines @@
                  base::Unretained(this)));
   web_ui()->RegisterMessageCallback("bubblePromoLinkClicked",
       base::Bind(&NewTabPageHandler::HandleBubblePromoLinkClicked,
                  base::Unretained(this)));
   web_ui()->RegisterMessageCallback("pageSelected",
       base::Bind(&NewTabPageHandler::HandlePageSelected,
                  base::Unretained(this)));
   web_ui()->RegisterMessageCallback("logTimeToClick",
       base::Bind(&NewTabPageHandler::HandleLogTimeToClick,
                  base::Unretained(this)));
+  web_ui()->RegisterMessageCallback("getShouldShowApps",
+      base::Bind(&NewTabPageHandler::HandleGetShouldShowApps,
+                 base::Unretained(this)));
 }
 
 void NewTabPageHandler::HandleNotificationPromoClosed(const ListValue* args) {
   UMA_HISTOGRAM_ENUMERATION("NewTabPage.Promo.Notification",
                             PROMO_CLOSED, PROMO_ACTION_MAX);
   NotificationPromo::HandleClosed(NotificationPromo::NTP_NOTIFICATION_PROMO);
   Notify(chrome::NOTIFICATION_PROMO_RESOURCE_STATE_CHANGED);
 }
 
 void NewTabPageHandler::HandleNotificationPromoViewed(const ListValue* args) {
@@ skipping 74 matching lines @@
     UMA_HISTOGRAM_LONG_TIMES(
         "ExtendedNewTabPage.TimeToClickMostVisited", delta);
   } else if (histogram_name == "ExtendedNewTabPage.TimeToClickRecentlyClosed") {
     UMA_HISTOGRAM_LONG_TIMES(
         "ExtendedNewTabPage.TimeToClickRecentlyClosed", delta);
   } else {
     NOTREACHED();
   }
 }
 
+void NewTabPageHandler::HandleGetShouldShowApps(const ListValue* args) {
+  extensions::UpdateIsAppLauncherEnabled(
+      base::Bind(&NewTabPageHandler::GotIsAppLauncherEnabled,
+                 AsWeakPtr()));
+}
+
+void NewTabPageHandler::GotIsAppLauncherEnabled(bool is_enabled) {
+  base::FundamentalValue should_show_apps(!is_enabled);
+  web_ui()->CallJavascriptFunction("ntp.gotShouldShowApps", should_show_apps);
+}
+
 // static
 void NewTabPageHandler::RegisterUserPrefs(PrefServiceSyncable* prefs) {
   // TODO(estade): should be syncable.
   prefs->RegisterIntegerPref(prefs::kNtpShownPage, APPS_PAGE_ID,
                              PrefServiceSyncable::UNSYNCABLE_PREF);
 }
 
 // static
 void NewTabPageHandler::GetLocalizedValues(Profile* profile,
                                            DictionaryValue* values) {
@@ skipping 11 matching lines @@
   values->SetInteger("shown_page_index", shown_page & INDEX_MASK);
 }
 
 void NewTabPageHandler::Notify(chrome::NotificationType notification_type) {
   content::NotificationService* service =
       content::NotificationService::current();
   service->Notify(notification_type,
                   content::Source<NewTabPageHandler>(this),
                   content::NotificationService::NoDetails());
 }