Add utf_string_conversions to base namespace.

chrome/browser/ui/webui/extensions/install_extension_handler.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/webui/extensions/install_extension_handler.h"
 
 #include "base/bind.h"
 #include "base/string_util.h"
 #include "base/utf_string_conversions.h"
 #include "chrome/browser/extensions/crx_installer.h"
@@ skipping 48 matching lines @@
     DLOG(ERROR) << "No current drop data.";
     return;
   }
 
   if (drop_data->filenames.empty()) {
     DLOG(ERROR) << "Current drop data contains no files.";
     return;
   }
 
   file_to_install_ = base::FilePath::FromWStringHack(
-      UTF16ToWide(drop_data->filenames.front().path));
+      base::UTF16ToWide(drop_data->filenames.front().path));
 }
 
 void InstallExtensionHandler::HandleStopDragMessage(const ListValue* args) {
   file_to_install_.clear();
 }
 
 void InstallExtensionHandler::HandleInstallMessage(const ListValue* args) {
   if (file_to_install_.empty()) {
     LOG(ERROR) << "No file captured to install.";
     return;
@@ skipping 23 matching lines @@
   } else if (EndsWith(file_to_install_.BaseName().value(),
                       FILE_PATH_LITERAL(".crx"),
                       kCaseSensitive)) {
     crx_installer->InstallCrx(file_to_install_);
   } else {
     CHECK(false);
   }
 
   file_to_install_.clear();
 }