cros: Add app mode restrictions.

ash/shell/shell_delegate_impl.h

Index: ash/shell/shell_delegate_impl.h
diff --git a/ash/shell/shell_delegate_impl.h b/ash/shell/shell_delegate_impl.h
index 311ebefe452f7888fc4ce8bf6d55a4f82fb23d7c..9ac2f78e6732e87821aae2323d6088957b80f86c 100644
--- a/ash/shell/shell_delegate_impl.h
+++ b/ash/shell/shell_delegate_impl.h
@@ -5,6 +5,8 @@
 #ifndef ASH_SHELL_SHELL_DELEGATE_IMPL_H_
 #define ASH_SHELL_SHELL_DELEGATE_IMPL_H_
 
+#include <string>
+
 #include "ash/shell_delegate.h"
 #include "base/compiler_specific.h"
 
@@ -24,6 +26,7 @@ class ShellDelegateImpl : public ash::ShellDelegate {
   virtual bool IsUserLoggedIn() const OVERRIDE;
   virtual bool IsSessionStarted() const OVERRIDE;
   virtual bool IsFirstRunAfterBoot() const OVERRIDE;
+  virtual bool IsRunningInForcedAppMode() const OVERRIDE;
   virtual bool CanLockScreen() const OVERRIDE;
   virtual void LockScreen() OVERRIDE;
   virtual void UnlockScreen() OVERRIDE;