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

chrome/common/pref_names.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/common/pref_names.h"
 
 #include "base/basictypes.h"
 
 namespace prefs {
 
@@ skipping 1562 matching lines @@
 // an extension ID and an update URL, delimited by a semicolon.
 // This preference is set by an admin policy, and meant to be only
 // accessed through extensions::ExternalPolicyProvider.
 const char kExtensionInstallForceList[] = "extensions.install.forcelist";
 
 // Indicates on-disk data might have skeletal data that needs to be cleaned
 // on the next start of the browser.
 const char kExtensionStorageGarbageCollect[] =
     "extensions.storage.garbagecollect";
 
+// Local state caching knowledge of whether the app launcher is installed.
+const char kAppLauncherIsEnabled[] =
+    "extensions.app_launcher.should_show_apps_page";
+
 // Keeps track of which sessions are collapsed in the Other Devices menu.
 const char kNtpCollapsedForeignSessions[] = "ntp.collapsed_foreign_sessions";
 
 // New Tab Page URLs that should not be shown as most visited thumbnails.
 const char kNtpMostVisitedURLsBlacklist[] = "ntp.most_visited_blacklist";
 
 // Last time of update of promo_resource_cache.
 const char kNtpPromoResourceCacheUpdate[] = "ntp.promo_resource_cache_update";
 
 // Serves tips for the NTP.
@@ skipping 637 matching lines @@
 const char kLastPolicyStatisticsUpdate[] = "policy.last_statistics_update";
 
 #if defined(OS_CHROMEOS)
 // The RLZ brand code, if enabled.
 const char kRLZBrand[] = "rlz.brand";
 // Whether RLZ pings are disabled.
 const char kRLZDisabled[] = "rlz.disabled";
 #endif
 
 }  // namespace prefs