Move --custom-launcher-page switch into app_list_switches.h.

ui/app_list/app_list_switches.cc

 // Copyright 2013 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 "ui/app_list/app_list_switches.h"
 
 #include "base/command_line.h"
 
 namespace app_list {
 namespace switches {
 
+// Specifies the chrome-extension:// URL for the contents of an additional page
+// added to the experimental app launcher.
+const char kCustomLauncherPage[] = "custom-launcher-page";
+
 // If set, the app info context menu item is not available in the app list UI.
 const char kDisableAppInfo[] = "disable-app-list-app-info";
 
 // If set, Drive apps will not be shown side-by-side with Chrome apps.
 const char kDisableDriveAppsInAppList[] = "disable-drive-apps-in-app-list";
 
 // Disables syncing of the app list independent of extensions.
 const char kDisableSyncAppList[] = "disable-sync-app-list";
 
 // If set, the app list will be centered and wide instead of tall.
@@ skipping 54 matching lines @@
 #if defined(OS_CHROMEOS)
   return !CommandLine::ForCurrentProcess()->HasSwitch(
       kDisableDriveAppsInAppList);
 #else
   return false;
 #endif
 }
 
 }  // namespace switches
 }  // namespace app_list