Added login screen mode for adding users into session.

chrome/browser/chromeos/login/login_display_host_impl.h

Index: chrome/browser/chromeos/login/login_display_host_impl.h
diff --git a/chrome/browser/chromeos/login/login_display_host_impl.h b/chrome/browser/chromeos/login/login_display_host_impl.h
index 162a9461926f1c8688353863f8a4940d916085c8..1d21d8dbb4a4178dac7ade6f1e35f2e951ffb119 100644
--- a/chrome/browser/chromeos/login/login_display_host_impl.h
+++ b/chrome/browser/chromeos/login/login_display_host_impl.h
@@ -53,7 +53,7 @@ class LoginDisplayHostImpl : public LoginDisplayHost,
   virtual WebUILoginView* GetWebUILoginView() const OVERRIDE;
   virtual views::Widget* GetWidget() const OVERRIDE;
   virtual void BeforeSessionStart() OVERRIDE;
-  virtual void OnSessionStart() OVERRIDE;
+  virtual void Finalize() OVERRIDE;
   virtual void OnCompleteLogin() OVERRIDE;
   virtual void OpenProxySettings() OVERRIDE;
   virtual void SetOobeProgressBarVisible(bool visible) OVERRIDE;
@@ -64,6 +64,8 @@ class LoginDisplayHostImpl : public LoginDisplayHost,
       const std::string& first_screen_name,
       scoped_ptr<DictionaryValue> screen_parameters) OVERRIDE;
   virtual WizardController* GetWizardController() OVERRIDE;
+  virtual void StartUserAdding(
+      const base::Closure& completion_callback) OVERRIDE;
   virtual void StartSignInScreen() OVERRIDE;
   virtual void ResumeSignInScreen() OVERRIDE;
   virtual void OnPreferencesChanged() OVERRIDE;
@@ -122,6 +124,9 @@ class LoginDisplayHostImpl : public LoginDisplayHost,
   // Closes |login_window_| and resets |login_window_| and |login_view_| fields.
   void ResetLoginWindowAndView();
 
+  // Returns true if hosr running UI for adding users into session.
+  bool IsRunningUserAdding();
+
   // Used to calculate position of the screens and background.
   gfx::Rect background_bounds_;
 
@@ -196,7 +201,8 @@ class LoginDisplayHostImpl : public LoginDisplayHost,
   enum {
     RESTORE_UNKNOWN,
     RESTORE_WIZARD,
-    RESTORE_SIGN_IN
+    RESTORE_SIGN_IN,
+    RESTORE_USER_ADDING,

[Nikita (slow), 2013/05/28 11:34:22]

nit: Let's rename it to something more specific like
Add user to session

[dzhioev (left Google), 2013/05/29 13:05:04]

Done.

   } restore_path_;
 
   // Stored parameters for StartWizard, required to restore in case of crash.
@@ -207,6 +213,9 @@ class LoginDisplayHostImpl : public LoginDisplayHost,
   // property of the root window for |login_window_|.
   bool old_ignore_solo_window_frame_painter_policy_value_;
 
+  // Called before host deletion.
+  base::Closure completion_callback_;
+
   DISALLOW_COPY_AND_ASSIGN(LoginDisplayHostImpl);
 };