z-order implemenation is incomplete for a mixing case

test/java/awt/ZOrder fails on jdk7 with option -Dsun.awt.disableMixing=true

The testcase attached to 6797487 can be used to reproduce the problem using standalone application.

New z-order implementation (introduced by 6809227) changes only the Z-order of the particular component upon addition (or removal, or z-order "change" request using setComponentZOrder) of the component.

The problem is that the new implementation does nothing on a z-order "change" request coming to a l/w container. And if the container contains some h/w children, then the z-order of the children will not be changed.

The problem is not visible when the mixing feature is enabled because the mixing implementation tracks all z-order "change" requests ifself. On Java level, the mixing have correct information about z-order for all components of hierarchy and it calculates correct shapes for all components affected by the z-order "change" request.

On native level, the z-order of the h/w components is incorrent in this case and this needs to be fixed.