Update all users of base::Version to explicitly specify the namespace, and clean up the header.

chrome/browser/extensions/updater/extension_downloader_delegate.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/browser/extensions/updater/extension_downloader_delegate.h"
 
 #include "base/logging.h"
-#include "base/version.h"
 
 namespace extensions {
 
 ExtensionDownloaderDelegate::PingResult::PingResult() : did_ping(false) {}
 
 ExtensionDownloaderDelegate::PingResult::~PingResult() {}
 
 ExtensionDownloaderDelegate::~ExtensionDownloaderDelegate() {}
 
 void ExtensionDownloaderDelegate::OnExtensionDownloadFailed(
     const std::string& id,
     ExtensionDownloaderDelegate::Error error,
     const ExtensionDownloaderDelegate::PingResult& ping_result,
     const std::set<int>& request_id) {}
 
 bool ExtensionDownloaderDelegate::GetPingDataForExtension(
     const std::string& id,
     ManifestFetchData::PingData* ping) {
   return false;
 }
 
 std::string ExtensionDownloaderDelegate::GetUpdateUrlData(
     const std::string& id) {
   return std::string();
 }
 
 }  // namespace extensions