Add best-effort/allow rollback flags on WorkItem.

chrome/installer/setup/app_launcher_installer.h

 // Copyright 2015 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.
 
 // The App Launcher is an adjunct product of Google Chrome, but it has a
 // distinct registry entry. The functions in this file tap into various points
 // in installer flow to update the App Launcher's registry, including the
 // removal of deprecated app commands. This concentrates ugly code to to one
 // place to facilitate future refactoring.
 
 #ifndef CHROME_INSTALLER_SETUP_APP_LAUNCHER_INSTALLER_H_
 #define CHROME_INSTALLER_SETUP_APP_LAUNCHER_INSTALLER_H_
 
-#if defined(GOOGLE_CHROME_BUILD)

[grt (UTC plus 2), 2016/05/16 18:55:01]

why remove this?

[fdoray, 2016/05/17 17:18:48]

To catch build errors before code reaches internal builders.

-
 #include <windows.h>
 
 namespace base {
 class FilePath;
-class Version;
 }  // namespace base
 
 class WorkItemList;
 
 namespace installer {
 
 class InstallerState;
 
-// Create Version key for a App Launcher (if not already present) and sets the
-// new product version as the last step.  We need this for App Launcher in
-// order for shadow registry key to work.
-void AddAppLauncherVersionKeyWorkItems(

[grt (UTC plus 2), 2016/05/16 18:55:01]

why mix the WI refactor with removing this code?

[fdoray, 2016/05/17 17:18:48]

created a separate CL https://codereview.chromium.org/1988683003/

-    HKEY root,
-    const base::Version& new_version,
-    bool add_language_identifier,
-    WorkItemList* list);
-
 // Remove App Launcher's registry key, so it is in sync with Google Chrome's.
 // Note: The key is added by App Launcher in SetDidRunForNDayActiveStats().
 void RemoveAppLauncherVersionKey(HKEY reg_root);
 
 // Adds work item to unconditionally remove legacy executables.
 void AddRemoveLegacyAppHostExeWorkItems(const base::FilePath& target_path,
                                         const base::FilePath& temp_path,
                                         WorkItemList* list);
 
-// Adds work item to unconditionally remove legacy app commands like
-// "install-application", "install-extension", and
-// "quick-enable-application-host".
-void AddRemoveLegacyAppCommandsWorkItems(
-    const InstallerState& installer_state,
-    WorkItemList* work_item_list);
-
 }  // namespace installer
 
-#endif  // defined(GOOGLE_CHROME_BUILD)
-
 #endif  // CHROME_INSTALLER_SETUP_APP_LAUNCHER_INSTALLER_H_