Update some uses of UTF conversions in chrome/browser to use the base:: namespace.

chrome/browser/autocomplete/shortcuts_provider_unittest.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/autocomplete/shortcuts_provider.h"
 
 #include <math.h>
 
 #include <algorithm>
 #include <functional>
@@ skipping 19 matching lines @@
 #include "chrome/browser/history/url_database.h"
 #include "chrome/common/pref_names.h"
 #include "chrome/test/base/testing_profile.h"
 #include "content/public/browser/notification_service.h"
 #include "content/public/test/test_browser_thread.h"
 #include "extensions/common/extension.h"
 #include "extensions/common/extension_builder.h"
 #include "extensions/common/value_builder.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
+using base::ASCIIToUTF16;
 
 // TestShortcutInfo -----------------------------------------------------------
 
 namespace {
 
 struct TestShortcutInfo {
   std::string guid;
   std::string text;
   std::string fill_into_edit;
   std::string destination_url;
@@ skipping 716 matching lines @@
   content::NotificationService::current()->Notify(
       chrome::NOTIFICATION_EXTENSION_UNLOADED,
       content::Source<Profile>(&profile_),
       content::Details<extensions::UnloadedExtensionInfo>(&details));
 
   // Now the URL should have disappeared.
   RunTest(text, false, ExpectedURLs(), std::string(), base::string16());
 }
 
 }  // namespace history