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

chrome/browser/metrics/chrome_browser_main_extra_parts_metrics.cc

 // Copyright (c) 2013 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/metrics/chrome_browser_main_extra_parts_metrics.h"
 
 #include <string>
 
 #include "base/bind.h"
 #include "base/command_line.h"
@@ skipping 135 matching lines @@
 
   // Record whether Chrome is the default browser or not.
   ShellIntegration::DefaultWebClientState default_state =
       ShellIntegration::GetDefaultBrowser();
   UMA_HISTOGRAM_ENUMERATION("DefaultBrowser.State", default_state,
                             ShellIntegration::NUM_DEFAULT_STATES);
 }
 
 void RecordLinuxGlibcVersion() {
 #if defined(OS_LINUX) && !defined(OS_CHROMEOS)
-  base::Version version(gnu_get_libc_version());
+  Version version(gnu_get_libc_version());
 
   UMALinuxGlibcVersion glibc_version_result = UMA_LINUX_GLIBC_NOT_PARSEABLE;
   if (version.IsValid() && version.components().size() == 2) {
     glibc_version_result = UMA_LINUX_GLIBC_UNKNOWN;
     uint32_t glibc_major_version = version.components()[0];
     uint32_t glibc_minor_version = version.components()[1];
     if (glibc_major_version == 2) {
       // A constant to translate glibc 2.x minor versions to their
       // equivalent UMALinuxGlibcVersion values.
       const int kGlibcMinorVersionTranslationOffset = 11 - UMA_LINUX_GLIBC_2_11;
@@ skipping 208 matching lines @@
   }
 }
 
 namespace chrome {
 
 void AddMetricsExtraParts(ChromeBrowserMainParts* main_parts) {
   main_parts->AddParts(new ChromeBrowserMainExtraPartsMetrics());
 }
 
 }  // namespace chrome