Add support for --critical-update-version to installer.

chrome/installer/util/install_util.cc

 // Copyright (c) 2011 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.
 //
 // See the corresponding header file for description of the functions in this
 // file.
 
 #include "chrome/installer/util/install_util.h"
 
 #include <shellapi.h>
@@ skipping 185 matching lines @@
 Version* InstallUtil::GetCriticalUpdateVersion(BrowserDistribution* dist,
                                                bool system_install) {
   DCHECK(dist);
   RegKey key;
   HKEY reg_root = (system_install) ? HKEY_LOCAL_MACHINE : HKEY_CURRENT_USER;
   LONG result =
       key.Open(reg_root, dist->GetVersionKey().c_str(), KEY_QUERY_VALUE);
 
   string16 version_str;
   if (result == ERROR_SUCCESS)
-    result = key.ReadValue(google_update::kRegCriticalUpdateField,
+    result = key.ReadValue(google_update::kRegCriticalVersionField,
                            &version_str);
 
   Version* ret = NULL;
   if (result == ERROR_SUCCESS && !version_str.empty()) {
     VLOG(1) << "Critical Update version for " << dist->GetApplicationName()
             << " found " << version_str;
     ret = Version::GetVersionFromString(WideToASCII(version_str));
   } else {
     DCHECK_EQ(ERROR_FILE_NOT_FOUND, result);
     VLOG(1) << "No existing " << dist->GetApplicationName()
@@ skipping 251 matching lines @@
   int len = GetDateFormatW(LOCALE_INVARIANT, 0, NULL, kDateFormat,
                            date_str, arraysize(date_str));
   if (len) {
     --len;  // Subtract terminating \0.
   } else {
     PLOG(DFATAL) << "GetDateFormat";
   }
 
   return std::wstring(date_str, len);
 }