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

chrome/common/chrome_content_client.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/common/chrome_content_client.h"
 
 #if defined(OS_LINUX)
 #include <fcntl.h>
 #endif  // defined(OS_LINUX)
 
@@ skipping 350 matching lines @@
   if (!base::ReadFileToString(manifest_path, &manifest_data))
     return false;
   scoped_ptr<base::Value> manifest_value(
       base::JSONReader::Read(manifest_data, base::JSON_ALLOW_TRAILING_COMMAS));
   if (!manifest_value.get())
     return false;
   base::DictionaryValue* manifest = NULL;
   if (!manifest_value->GetAsDictionary(&manifest))
     return false;
 
-  base::Version version;
+  Version version;
   if (!chrome::CheckPepperFlashManifest(*manifest, &version))
     return false;
 
   *plugin = CreatePepperFlashInfo(flash_filename, version.GetString());
   return true;
 }
 #endif  //  defined(ENABLE_PLUGINS)
 
 std::string GetProduct() {
   return version_info::GetProductNameAndVersionForUserAgent();
@@ skipping 66 matching lines @@
 #endif
 }
 
 #if defined(ENABLE_PLUGINS)
 // static
 content::PepperPluginInfo* ChromeContentClient::FindMostRecentPlugin(
     const std::vector<content::PepperPluginInfo*>& plugins) {
   auto it = std::max_element(
       plugins.begin(), plugins.end(),
       [](content::PepperPluginInfo* x, content::PepperPluginInfo* y) {
-        base::Version version_x(x->version);
+        Version version_x(x->version);
         DCHECK(version_x.IsValid());
         return version_x.IsOlderThan(y->version);
       });
   return it != plugins.end() ? *it : nullptr;
 }
 #endif  // defined(ENABLE_PLUGINS)
 
 void ChromeContentClient::AddPepperPlugins(
     std::vector<content::PepperPluginInfo>* plugins) {
 #if defined(ENABLE_PLUGINS)
@@ skipping 118 matching lines @@
   schemes->insert(content::kChromeUIScheme);
   schemes->insert(extensions::kExtensionScheme);
   schemes->insert(extensions::kExtensionResourceScheme);
   GetSecureOriginWhitelist(origins);
 }
 
 void ChromeContentClient::AddServiceWorkerSchemes(
     std::set<std::string>* schemes) {
   schemes->insert(extensions::kExtensionScheme);
 }