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

chrome/browser/ui/cocoa/infobars/mock_confirm_infobar_delegate.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/cocoa/infobars/mock_confirm_infobar_delegate.h"
 
 #include "base/strings/utf_string_conversions.h"
 
 const char MockConfirmInfoBarDelegate::kMessage[] = "MockConfirmInfoBarMessage";
 
@@ skipping 14 matching lines @@
     owner_->OnInfoBarDelegateClosed();
 }
 
 int MockConfirmInfoBarDelegate::GetIconID() const {
   icon_accessed_ = true;
   return kNoIconID;
 }
 
 base::string16 MockConfirmInfoBarDelegate::GetMessageText() const {
   message_text_accessed_ = true;
-  return ASCIIToUTF16(kMessage);
+  return base::ASCIIToUTF16(kMessage);
 }
 
 base::string16 MockConfirmInfoBarDelegate::GetButtonLabel(
     InfoBarButton button) const {
-  return ASCIIToUTF16((button == BUTTON_OK) ? "OK" : "Cancel");
+  return base::ASCIIToUTF16((button == BUTTON_OK) ? "OK" : "Cancel");
 }
 
 bool MockConfirmInfoBarDelegate::Accept() {
   ok_clicked_ = true;
   return closes_on_action_;
 }
 
 bool MockConfirmInfoBarDelegate::Cancel() {
   cancel_clicked_ = true;
   return closes_on_action_;
 }
 
 base::string16 MockConfirmInfoBarDelegate::GetLinkText() const {
   link_text_accessed_ = true;
   return base::string16();
 }
 
 bool MockConfirmInfoBarDelegate::LinkClicked(
     WindowOpenDisposition disposition) {
   link_clicked_ = true;
   return closes_on_action_;
 }