Visiblity changes are processed in wrong order

Steps to reproduce:

1. Create a subtree of 1000 VE (background color) with 1 child each (e.g. text).
2. Set visibility:hidden on the 1000 VE
3. Continue for 1 frame
4. Toggle visibility to visible
5. Observe the number of draw calls

Actual results: 

Thousands of draw ranges

Expected results: 

Draw ranges should be minimal

Notes:

This is caused by the parents being visited first, so all background get generated and only then will the text be generated. This is incoherent with the draw order which is depth-first pre-order.

See also:

https://discussions.unity.com/t/ui-toolkit-render-data-regenerated-out-of-paint-order-after-visibility-hidden-geometry-artifact/1736958