ScreenObserver is renamed to BaseScreenDelegate.

chrome/browser/chromeos/login/screens/base_screen_delegate.h

 // 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.
 
-#ifndef CHROME_BROWSER_CHROMEOS_LOGIN_SCREENS_SCREEN_OBSERVER_H_
-#define CHROME_BROWSER_CHROMEOS_LOGIN_SCREENS_SCREEN_OBSERVER_H_
+#ifndef CHROME_BROWSER_CHROMEOS_LOGIN_SCREENS_BASE_SCREEN_DELEGATE_H_
+#define CHROME_BROWSER_CHROMEOS_LOGIN_SCREENS_BASE_SCREEN_DELEGATE_H_
 
 #include <string>
 
 namespace chromeos {
 
 class ErrorScreen;
 class BaseScreen;
 
 // Interface that handles notifications received from any of login wizard
 // screens.
-class ScreenObserver {
+class BaseScreenDelegate {
  public:
   // Each login screen or a view shown within login wizard view is itself a
   // state. Upon exit each view returns one of the results by calling OnExit()
   // method. Depending on the result and the current view or state login wizard
   // decides what is the next view to show. There must be an exit code for each
   // way to exit the screen for each screen. (Numeric ids are provided to
   // facilitate interpretation of log files only, they are subject to change
   // without notice.)
   enum ExitCodes {
     // "Continue" was pressed on network screen and network is online.
@@ skipping 29 matching lines @@
   virtual void OnExit(ExitCodes exit_code) = 0;
 
   // Forces current screen showing.
   virtual void ShowCurrentScreen() = 0;
 
   virtual ErrorScreen* GetErrorScreen() = 0;
   virtual void ShowErrorScreen() = 0;
   virtual void HideErrorScreen(BaseScreen* parent_screen) = 0;
 
  protected:
-  virtual ~ScreenObserver() {}
+  virtual ~BaseScreenDelegate() {}
 };
 
 }  // namespace chromeos
 
-#endif  // CHROME_BROWSER_CHROMEOS_LOGIN_SCREENS_SCREEN_OBSERVER_H_
+#endif  // CHROME_BROWSER_CHROMEOS_LOGIN_SCREENS_BASE_SCREEN_DELEGATE_H_