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

chrome/common/service_process_util_mac.mm

 // 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/common/service_process_util_posix.h"
 
 #import <Foundation/Foundation.h>
 #include <launch.h>
 
 #include <vector>
@@ skipping 185 matching lines @@
   base::FileDescriptor fd(socket, false);
   return IPC::ChannelHandle(std::string(), fd);
 }
 
 bool CheckServiceProcessReady() {
   std::string version;
   pid_t pid;
   if (!GetServiceProcessData(&version, &pid)) {
     return false;
   }
-  base::Version service_version(version);
+  Version service_version(version);
   bool ready = true;
   if (!service_version.IsValid()) {
     ready = false;
   } else {
-    base::Version running_version(version_info::GetVersionNumber());
+    Version running_version(version_info::GetVersionNumber());
     if (!running_version.IsValid()) {
       // Our own version is invalid. This is an error case. Pretend that we
       // are out of date.
       NOTREACHED();
       ready = true;
     } else if (running_version.CompareTo(service_version) > 0) {
       ready = false;
     } else {
       ready = true;
     }
@@ skipping 214 matching lines @@
       CFErrorRef err = NULL;
       if (!Launchd::GetInstance()->RemoveJob(label, &err)) {
         base::ScopedCFTypeRef<CFErrorRef> scoped_err(err);
         DLOG(ERROR) << "RemoveJob " << err;
         // Exiting with zero, so launchd doesn't restart the process.
         exit(0);
       }
     }
   }
 }