ViaVersion

3951cff Cancel out unmapped (block) ids in HolderSetImpl (#4512)

In VB, mapping data will return -1 for missing block ids (which is for almost all blocks the case). This is made so that VV rewriters can cancel these blocks away nicely (as mostly used in places where it's better to show the user nothing rather than wrong blocks, such as statistics).

Fixes https://github.com/ViaVersion/ViaVersion/issues/4510