[cleanup] Make FirstClassCallableRector use attributes over node traverser hacks

[TomasVotruba]

No description provided.

[samsonasik]

I am not sure about this, this may cause issue on performance, since it adds new "preload" attribute whether used or not, and people tend to use big data on property/constant.

The previous implementation will only set below node on specific rule, now this set attribute on any rule.

[TomasVotruba]

I'll give it a test run for performance, but I think we'll be safe.
Goal is to remove all int return types from refactor() as that give us extra complexity in AbstractRector

[TomasVotruba]

Seems no diff at all. Mind the NodeVisitor::DONT_TRAVERSE_* triggers node traverser on all nodes + its children as well. Goal of this is to remove it and re-use attribute-flags instead. Those can be shared as well 👍

before

387.88s user 7.07s system 1778% cpu 22.207 total
351.04s user 6.39s system 1735% cpu 20.598 total

after

376.07s user 6.51s system 1716% cpu 22.291 total
361.87s user 6.76s system 1697% cpu 21.714 total
343.33s user 6.33s system 1644% cpu 21.268 total