[API REVIEW] RT-30576 Parent : add new public layout method, optimized to only layout this parent and it's children.

[mick.fleming]

Hi Martin,

> I would like to introduce similar call, see 

it's a shame about the overlap, but at least I
assume it means that we're in agreement that
something can be done here :-)

There does seem to be a a difference between the
two. While your requestParentLayout doesn't clear
the size cache, it does go up the hierarchy.
My proposal is for a method that specifically
doesn't request a layout up the hierarchy, and
only sets the current Parent as dirty. There are
cases where it's know that the change is only local.
My change is aimed primarily at Controls and the like,
for cases where they've changed their internals, and it's
known that there is no knock-on effect.

I have an implementation, that includes changes to
Controls, Charts and Layout to utilize it.


regards,
mick