8160974: [TESTBUG] Mark more headful tests with @key headful.
Reviewed-by: serb, simonis

7041387: Introduce new boolean system property java.awt.smartInvalidate
Summary: The behavior introduced with 6852592 is now enabled by the new system property only
Reviewed-by: dcherepanov

7036669: Simplify revalidating component hierarchy with multiple validate roots
Summary: Introduce Component.revalidate() method
Reviewed-by: art, alexp