Always do DelegateExecute handler COM registration and make set dual mode prop on shortcuts.

chrome/installer/util/shell_util.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.
 //
 // This file defines functions that integrate Chrome in Windows shell. These
 // functions can be used by Chrome as well as Chrome installer. All of the
 // work is done by the local functions defined in anonymous namespace in
 // this class.
 
 #include "chrome/installer/util/shell_util.h"
@@ skipping 74 matching lines @@
     string16 icon_path(ShellUtil::GetChromeIcon(dist, chrome_exe));
     string16 open_cmd(ShellUtil::GetChromeShellOpenCmd(chrome_exe));
     string16 delegate_command(ShellUtil::GetChromeDelegateCommand(chrome_exe));
     // For user-level installs: entries for the app id and DelegateExecute verb
     // handler will be in HKCU; thus we do not need a suffix on those entries.
     string16 app_id(dist->GetBrowserAppId());
     string16 delegate_guid;
     // TODO(grt): remove HasDelegateExecuteHandler when the exe is ever-present;
     // see also install_worker.cc's AddDelegateExecuteWorkItems.
     bool set_delegate_execute =
+        base::win::GetVersion() >= base::win::VERSION_WIN8 &&
         dist->GetDelegateExecuteHandlerData(&delegate_guid, NULL, NULL, NULL) &&
         InstallUtil::HasDelegateExecuteHandler(dist, chrome_exe);
 
     // DelegateExecute ProgId. Needed for Chrome Metro in Windows 8.
     if (set_delegate_execute) {
       string16 model_id_shell(ShellUtil::kRegClasses);
       model_id_shell.push_back(FilePath::kSeparators[0]);
       model_id_shell.append(app_id);
       model_id_shell.append(ShellUtil::kRegExePath);
       model_id_shell.append(ShellUtil::kRegShellPath);
@@ skipping 1155 matching lines @@
       chrome_exe.c_str(),
       shortcut.c_str(),
       chrome_path.c_str(),
       arguments.c_str(),
       description.c_str(),
       icon_path.c_str(),
       icon_index,
       dist->GetBrowserAppId().c_str(),
       ConvertShellUtilShortcutOptionsToFileUtil(options));
 }