cros: Explicitly manage app session lifetime.

chrome/browser/chromeos/app_mode/startup_app_launcher.h

Index: chrome/browser/chromeos/app_mode/startup_app_launcher.h
diff --git a/chrome/browser/chromeos/app_mode/startup_app_launcher.h b/chrome/browser/chromeos/app_mode/startup_app_launcher.h
index 8d63387bc3baa6f39a700eefaab8b9ea8cec150d..be503ade3b720ed8a03365d14c4c9c7de9079cb5 100644
--- a/chrome/browser/chromeos/app_mode/startup_app_launcher.h
+++ b/chrome/browser/chromeos/app_mode/startup_app_launcher.h
@@ -9,6 +9,7 @@
 
 #include "base/basictypes.h"
 #include "base/memory/ref_counted.h"
+#include "base/memory/scoped_ptr.h"
 #include "base/memory/weak_ptr.h"
 #include "base/timer.h"
 #include "chrome/browser/chromeos/app_mode/kiosk_app_launch_error.h"
@@ -54,6 +55,9 @@ class StartupAppLauncher
     std::string client_secret;
   };
 
+  // A class to watch for app window creation.
+  class AppWindowWatcher;
+
   // Private dtor because this class manages its own lifetime.
   virtual ~StartupAppLauncher();
 
@@ -97,6 +101,8 @@ class StartupAppLauncher
   base::OneShotTimer<StartupAppLauncher> network_wait_timer_;
   KioskOAuthParams auth_params_;
 
+  scoped_ptr<AppWindowWatcher> app_window_watcher_;
+
   DISALLOW_COPY_AND_ASSIGN(StartupAppLauncher);
 };