Upstream has released updates that appears to apply and compile correctly.
This update has not been tested by PaperMC and as with ANY update, please do your own testing
Bukkit Changes:
5d4de46e Fix checkstyle.xml formatting
adf331f1 SPIGOT-5496: API to create and manipulate hardcore worlds
CraftBukkit Changes:
c727dc2a Fix checkstyle.xml formatting
e7202cd4 SPIGOT-5496: API to create and manipulate hardcore worlds
9820cd2d MC-151364, SPIGOT-5494: Feeding dolphin hangs if generate-structures=false
69f05b3132