cros: Remove unused method

chrome/browser/chromeos/login/screens/enable_debugging_screen.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/chromeos/login/screens/enable_debugging_screen.h"
 
 #include "base/logging.h"
 #include "chrome/browser/chromeos/login/screens/base_screen_delegate.h"
 #include "chrome/browser/chromeos/login/wizard_controller.h"
 
 namespace chromeos {
 
 EnableDebuggingScreen::EnableDebuggingScreen(
     BaseScreenDelegate* delegate,
     EnableDebuggingScreenActor* actor)
     : BaseScreen(delegate), actor_(actor) {
   DCHECK(actor_);
   if (actor_)
     actor_->SetDelegate(this);
 }
 
 EnableDebuggingScreen::~EnableDebuggingScreen() {
   if (actor_)
     actor_->SetDelegate(NULL);
 }
 
-void EnableDebuggingScreen::PrepareToShow() {
-  if (actor_)
-    actor_->PrepareToShow();
-}
-
 void EnableDebuggingScreen::Show() {
   if (actor_)
     actor_->Show();
 }
 
 void EnableDebuggingScreen::Hide() {
   if (actor_)
     actor_->Hide();
 }
 
 std::string EnableDebuggingScreen::GetName() const {
   return WizardController::kEnableDebuggingScreenName;
 }
 
 void EnableDebuggingScreen::OnExit(bool success) {
   Finish(success ? BaseScreenDelegate::ENABLE_DEBUGGING_FINISHED :
                    BaseScreenDelegate::ENABLE_DEBUGGING_CANCELED);
 }
 
 void EnableDebuggingScreen::OnActorDestroyed(
     EnableDebuggingScreenActor* actor) {
   if (actor_ == actor)
     actor_ = NULL;
 }
 
 }  // namespace chromeos