* Fix infinite layout loop
- The problem will occur if a node does either of the followings:
1. Keeps using a stale pending layout over a calculated layout
2. Doesn't update the next layout's version after calling _setNeedsLayoutFromAbove.
* Update CHANGELOG
I believe this check is supposed to be here. Unit tests pass with it in place.
Without it, calling layoutThatFits: (as ASDataController does) and then calling
it again later (as ASCollectionNode does when answering the sizeForItem: call)
will recompute the layout, potentially on main.
This seems to have more of an impact / benefit for Yoga layouts, but I don't think
its benefit is exclusive to them.
This ensures that measure funcs are not set for container / empty spacer
nodes, because Yoga has more internal capabilities than layoutThatFits:
knows about.
Avoid need for the main layout pass to directly call setup for measure
funcs, by making it an implicit part of .yogaLayoutInProgress =.
Tear down the measure func after the layout pass to avoid retain cycle.
This has one important benefit: fixing the stretching behavior of spacer nodes.
In addition, it should help efficiency of Yoga and certainly minimize calls
to layoutThatFits:.
Next up for Yoga is a mostly-red diff, deleting the non-Contiguous code branches.
* [ASTraitCollection] Convert ASPrimitiveTraitCollection from lock to atomic.
This resolves a deadlock case: https://github.com/TextureGroup/Texture/issues/353
* [ASTraitCollection] Use assignment operator instead of .store() for C++ atomic.
* Small changes required by the layout debugger
- `ASDisplayNode` can be told to not flatten its layout immediately but later on. The unflattened layout is also stored in a separate property. It's needed for inspecting not only display nodes but also layout specs used to compute a layout tree.
- `ASLayout` can be told to always retain its sublayout elements. This is needed especially for layout specs since they are usually not retained after an ASLayout was computed.
* Update CHANGELOG
* Address comments
It is rare that this code has any effect, but I've discovered a case in which it occurs.
This task tracks moving this code to a DEBUG-only assertion: https://github.com/TextureGroup/Texture/issues/335
