{
final ChildVariant1 x = (ChildVariant1) this.element.getHeterogeneous().content( true, ChildVariant1.TYPE );
assertNotNull( x );
final ChildVariant2 y = (ChildVariant2) this.element.getHeterogeneous().content( true, ChildVariant2.TYPE );
assertNotNull( y );
assertTrue( x.disposed() );
}