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

components/update_client/update_client.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.
 
 #ifndef COMPONENTS_UPDATE_CLIENT_UPDATE_CLIENT_H_
 #define COMPONENTS_UPDATE_CLIENT_UPDATE_CLIENT_H_
 
 #include <stdint.h>
 #include <string>
 #include <vector>
@@ skipping 170 matching lines @@
 struct CrxComponent {
   CrxComponent();
   ~CrxComponent();
 
   // SHA256 hash of the CRX's public key.
   std::vector<uint8_t> pk_hash;
   scoped_refptr<CrxInstaller> installer;
 
   // The current version if the CRX is updated. Otherwise, "0" or "0.0" if
   // the CRX is installed.
-  base::Version version;
+  Version version;
 
   std::string fingerprint;  // Optional.
   std::string name;         // Optional.
 
   // Specifies that the CRX can be background-downloaded in some cases.
   // The default for this value is |true| and the value can be overriden at
   // the registration time. This is a temporary change until the issue
   // crbug/340448 is resolved.
   bool allow_background_download;
 };
@@ skipping 90 matching lines @@
   virtual ~UpdateClient() {}
 };
 
 // Creates an instance of the update client.
 scoped_refptr<UpdateClient> UpdateClientFactory(
     const scoped_refptr<Configurator>& config);
 
 }  // namespace update_client
 
 #endif  // COMPONENTS_UPDATE_CLIENT_UPDATE_CLIENT_H_