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

chrome/browser/ui/startup/default_browser_prompt.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/ui/startup/default_browser_prompt.h"
 
 #include "base/location.h"
 #include "base/memory/weak_ptr.h"
 #include "base/metrics/histogram.h"
 #include "base/prefs/pref_registry_simple.h"
@@ skipping 249 matching lines @@
       // TODO(pastarmovj): We can't really do anything meaningful here yet but
       // just prevent showing the infobar.
     }
     return;
   }
 
   if (show_prompt) {
     const std::string disable_version_string =
         g_browser_process->local_state()->GetString(
             prefs::kBrowserSuppressDefaultBrowserPrompt);
-    const base::Version disable_version(disable_version_string);
+    const Version disable_version(disable_version_string);
     DCHECK(disable_version_string.empty() || disable_version.IsValid());
     if (disable_version.IsValid()) {
-      if (disable_version.Equals(
-              base::Version(version_info::GetVersionNumber())))
+      if (disable_version.Equals(Version(version_info::GetVersionNumber())))
         show_prompt = false;
     }
   }
 
   content::BrowserThread::PostTask(
       content::BrowserThread::FILE, FROM_HERE,
       base::Bind(&CheckDefaultBrowserOnFileThread, profile->GetPath(),
                  show_prompt, desktop_type));
 }
 
 #if !defined(OS_WIN)
 bool ShowFirstRunDefaultBrowserPrompt(Profile* profile) {
   return false;
 }
 #endif
 
 }  // namespace chrome