Revert of base: Remove using:: declaration from version.h header.

chrome/installer/setup/setup_main.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/installer/setup/setup_main.h"
 
 #include <windows.h>
 #include <msi.h>
 #include <shellapi.h>
 #include <shlobj.h>
@@ skipping 876 matching lines @@
     shortcut_properties.set_pin_to_taskbar(true);
     shortcut_properties.set_pin_to_start(true);
     ShellUtil::CreateOrUpdateShortcut(
         ShellUtil::SHORTCUT_LOCATION_START_MENU_CHROME_DIR, chrome_dist,
         shortcut_properties, ShellUtil::SHELL_SHORTCUT_CREATE_ALWAYS);
 
     // Register Chrome at user-level and make it default.
     scoped_ptr<WorkItemList> delegate_execute_list(
         WorkItem::CreateWorkItemList());
     installer::AddDelegateExecuteWorkItems(
-        installer_state, chrome_exe.DirName(), base::Version(), chrome,
+        installer_state, chrome_exe.DirName(), Version(), chrome,
         delegate_execute_list.get());
     delegate_execute_list->Do();
     if (ShellUtil::CanMakeChromeDefaultUnattended()) {
       ShellUtil::MakeChromeDefault(chrome_dist, ShellUtil::CURRENT_USER,
                                    chrome_exe, true);
     } else {
       ShellUtil::ShowMakeChromeDefaultSystemUI(chrome_dist, chrome_exe);
     }
   } else {
     LOG(ERROR) << "Path not found: " << chrome_exe.value();
@@ skipping 210 matching lines @@
       }
     }
   } else if (cmd_line.HasSwitch(installer::switches::kSystemLevelToast)) {
     const Products& products = installer_state->products();
     for (Products::const_iterator it = products.begin(); it < products.end();
          ++it) {
       const Product& product = **it;
       BrowserDistribution* browser_dist = product.distribution();
       // We started as system-level and have been re-launched as user level
       // to continue with the toast experiment.
-      base::Version installed_version;
+      Version installed_version;
       InstallUtil::GetChromeVersion(browser_dist, true, &installed_version);
       if (!installed_version.IsValid()) {
         LOG(ERROR) << "No installation of "
                    << browser_dist->GetDisplayName()
                    << " found for system-level toast.";
       } else {
         product.LaunchUserExperiment(
             setup_exe, installer::REENTRY_SYS_UPDATE, true);
       }
     }
@@ skipping 243 matching lines @@
                               unpack_path.value(),
                               NULL)) {
     installer_state.WriteInstallerResult(
         UNPACKING_FAILED,
         IDS_INSTALL_UNCOMPRESSION_FAILED_BASE,
         NULL);
     return UNPACKING_FAILED;
   }
 
   VLOG(1) << "unpacked to " << unpack_path.value();
-  base::FilePath src_path(unpack_path.Append(kInstallSourceChromeDir));
-  scoped_ptr<base::Version>
+  base::FilePath src_path(
+      unpack_path.Append(kInstallSourceChromeDir));
+  scoped_ptr<Version>
       installer_version(GetMaxVersionFromArchiveDir(src_path));
   if (!installer_version.get()) {
     LOG(ERROR) << "Did not find any valid version in installer.";
     install_status = INVALID_ARCHIVE;
     installer_state.WriteInstallerResult(install_status,
         IDS_INSTALL_INVALID_ARCHIVE_BASE, NULL);
   } else {
     VLOG(1) << "version to install: " << installer_version->GetString();
     bool proceed_with_installation = true;
 
@@ skipping 305 matching lines @@
     // Note that we allow the status installer::UNINSTALL_REQUIRES_REBOOT
     // to pass through, since this is only returned on uninstall which is
     // never invoked directly by Google Update.
     return_code = InstallUtil::GetInstallReturnCode(install_status);
   }
 
   VLOG(1) << "Installation complete, returning: " << return_code;
 
   return return_code;
 }