Use utf_string_conversions header in more places.

app/clipboard/scoped_clipboard_writer.cc

 // Copyright (c) 2009 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.
 
 // This file implements the ScopedClipboardWriter class. Documentation on its
 // purpose can be found in our header. Documentation on the format of the
 // parameters for each clipboard target can be found in clipboard.h.
 
 #include "app/clipboard/scoped_clipboard_writer.h"
 
 #include "base/gfx/size.h"
 #include "base/pickle.h"
-#include "base/string_util.h"
+#include "base/utf_string_conversions.h"
 
 ScopedClipboardWriter::ScopedClipboardWriter(Clipboard* clipboard)
     : clipboard_(clipboard) {
 }
 
 ScopedClipboardWriter::~ScopedClipboardWriter() {
   if (!objects_.empty() && clipboard_) {
     clipboard_->WriteObjects(objects_);
     if (url_text_.length())
       clipboard_->DidWriteURL(url_text_);
@@ skipping 104 matching lines @@
                                                  utf8_text.end()));
   objects_[Clipboard::CBF_TEXT] = parameters;
 
   if (is_url) {
     url_text_ = utf8_text;
   } else {
     url_text_.clear();
   }
 }