cros: Break BaseScreenHandler into two classes.

chrome/browser/ui/webui/chromeos/login/wrong_hwid_screen_handler.cc

 // Copyright (c) 2013 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/chromeos/login/wrong_hwid_screen_handler.h"
 
 #include "chrome/browser/chromeos/login/oobe_screen.h"
 #include "chrome/grit/generated_resources.h"
 #include "components/login/localized_values_builder.h"
 
 namespace {
 
 const char kJsScreenPath[] = "login.WrongHWIDScreen";
 
 }  // namespace
 
 namespace chromeos {
 
-WrongHWIDScreenHandler::WrongHWIDScreenHandler() {
+WrongHWIDScreenHandler::WrongHWIDScreenHandler()
+    : BaseScreenHandler(kScreenId) {
   set_call_js_prefix(kJsScreenPath);
 }
 
 WrongHWIDScreenHandler::~WrongHWIDScreenHandler() {
   if (delegate_)
     delegate_->OnViewDestroyed(this);
 }
 
 void WrongHWIDScreenHandler::Show() {
   if (!page_is_ready()) {
     show_on_init_ = true;
     return;
   }
-  ShowScreen(OobeScreen::SCREEN_WRONG_HWID);
+  ShowScreen(kScreenId);
 }
 
 void WrongHWIDScreenHandler::Hide() {
 }
 
 void WrongHWIDScreenHandler::SetDelegate(Delegate* delegate) {
   delegate_ = delegate;
   if (page_is_ready())
     Initialize();
 }
@@ skipping 22 matching lines @@
 void WrongHWIDScreenHandler::RegisterMessages() {
   AddCallback("wrongHWIDOnSkip", &WrongHWIDScreenHandler::HandleOnSkip);
 }
 
 void WrongHWIDScreenHandler::HandleOnSkip() {
   if (delegate_)
     delegate_->OnExit();
 }
 
 }  // namespace chromeos