Save display preference on boot

chrome/browser/ui/ash/chrome_shell_delegate.h

Index: chrome/browser/ui/ash/chrome_shell_delegate.h
diff --git a/chrome/browser/ui/ash/chrome_shell_delegate.h b/chrome/browser/ui/ash/chrome_shell_delegate.h
index 344965dd0abeae2c9ac6c4c4062500c08c5f8fb1..e9b46a4f802041ea4899b09227b61d4ccc70412c 100644
--- a/chrome/browser/ui/ash/chrome_shell_delegate.h
+++ b/chrome/browser/ui/ash/chrome_shell_delegate.h
@@ -29,6 +29,12 @@ namespace keyboard {
 class KeyboardControllerProxy;
 }
 
+#if defined(OS_CHROMEOS)
+namespace chromeos {
+class DisplayConfigurationObserver;
+}
+#endif
+
 class ChromeLauncherController;
 
 class ChromeShellDelegate : public ash::ShellDelegate,
@@ -82,6 +88,11 @@ class ChromeShellDelegate : public ash::ShellDelegate,
 
   ChromeLauncherController* shelf_delegate_;
 
+#if defined(OS_CHROMEOS)
+  scoped_ptr<chromeos::DisplayConfigurationObserver>
+      display_configuration_observer_;
+#endif
+
   DISALLOW_COPY_AND_ASSIGN(ChromeShellDelegate);
 };