CppTools: Fix compilation with Qt4

Change-Id: I76c6ea3557c46fbca4ccb0fb293c6ed6f03e96df
Reviewed-by: Orgad Shaneh <orgads@gmail.com>
Reviewed-by: Robert Loehning <robert.loehning@digia.com>
Reviewed-by: Erik Verbruggen <erik.verbruggen@digia.com>