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

extensions/common/update_manifest.cc

 // Copyright 2014 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 "extensions/common/update_manifest.h"
 
 #include <algorithm>
 
 #include "base/memory/scoped_ptr.h"
 #include "base/stl_util.h"
@@ skipping 149 matching lines @@
     *error_detail += "'.";
     return false;
   }
 
   // Get the version.
   result->version = GetAttribute(updatecheck, "version");
   if (result->version.length() == 0) {
     *error_detail = "Missing version for updatecheck.";
     return false;
   }
-  base::Version version(result->version);
+  Version version(result->version);
   if (!version.IsValid()) {
     *error_detail = "Invalid version: '";
     *error_detail += result->version;
     *error_detail += "'.";
     return false;
   }
 
   // Get the minimum browser version (not required).
   result->browser_min_version = GetAttribute(updatecheck, "prodversionmin");
   if (result->browser_min_version.length()) {
-    base::Version browser_min_version(result->browser_min_version);
+    Version browser_min_version(result->browser_min_version);
     if (!browser_min_version.IsValid()) {
       *error_detail = "Invalid prodversionmin: '";
       *error_detail += result->browser_min_version;
       *error_detail += "'.";
       return false;
     }
   }
 
   // package_hash is optional. It is a sha256 hash of the package in hex
   // format.
@@ skipping 84 matching lines @@
     std::string error;
     if (!ParseSingleAppTag(apps[i], gupdate_ns, &current, &error)) {
       ParseError("%s", error.c_str());
     } else {
       results_.list.push_back(current);
     }
   }
 
   return true;
 }