[cros] Change how we track momemt to emit login-prompt-visible signal.

chrome/browser/ui/webui/chromeos/login/signin_screen_handler.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_UI_WEBUI_CHROMEOS_LOGIN_SIGNIN_SCREEN_HANDLER_H_
 #define CHROME_BROWSER_UI_WEBUI_CHROMEOS_LOGIN_SIGNIN_SCREEN_HANDLER_H_
 #pragma once
 
 #include <string>
 
@@ skipping 191 matching lines @@
   void HandleCreateAccount(const base::ListValue* args);
   void HandleAccountPickerReady(const base::ListValue* args);
   void HandleLoginWebuiReady(const base::ListValue* args);
   void HandleLoginRequestNetworkState(const base::ListValue* args);
   void HandleLoginAddNetworkStateObserver(const base::ListValue* args);
   void HandleLoginRemoveNetworkStateObserver(const base::ListValue* args);
   void HandleSignOutUser(const base::ListValue* args);
   void HandleUserImagesLoaded(const base::ListValue* args);
   void HandleNetworkErrorShown(const base::ListValue* args);
   void HandleOpenProxySettings(const base::ListValue* args);
+  void HandleLoginVisible(const base::ListValue* args);
 
   // Sends user list to account picker.
   void SendUserList(bool animated);
 
   // Kick off cookie / local storage cleanup.
   void StartClearingCookies();
 
   // Kick off DNS cache flushing.
   void StartClearingDnsCache();
   void OnDnsCleared();
@@ skipping 53 matching lines @@
   BrowsingDataRemover* cookie_remover_;
 
   base::WeakPtrFactory<SigninScreenHandler> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(SigninScreenHandler);
 };
 
 }  // namespace chromeos
 
 #endif  // CHROME_BROWSER_UI_WEBUI_CHROMEOS_LOGIN_SIGNIN_SCREEN_HANDLER_H_