When a BP changes, the BP value changes, the propertyChanged event is
fired, then the propertyChanged delegate is executed.
As the invalidation was done in the event, and setting the flexitem
property was done in the delegate, the invalidation, and relayout, was
executed with an out-of-date flexitem.
With this change, we invalidate the child size, and that'll bubble up to
invalidate the layout, as part of the property changed delegate
- fixes#2821
* [C] FlexLayout, with managed engine
* [C] add type converter and attributes for CSS
* [C] fix flex-order
* [C] fix typo and margin in Flex
* [Flex] relative value for Basis, padding on the layout
* fix docs
* [Flex] fix NRE on empty layout
* [flex] fix layout measuring
Stephane Delcroix
E.Z. Hart