Looking over the code, this appears to be one "high risk but hopefully
unlikely that plugins are causing this to break", this line is however
redundant leftovers from spigots tick limiter patch, which should be
doing nothing as-is.
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:
da08d022 SPIGOT-4700: Add PlayerFishEvent.State.REEL_IN
0cef14e4 Remove draft API from selectEntities
CraftBukkit Changes:
a46fdbc6 Remove outdated build delay.
3697519b SPIGOT-4708: Fix ExactChoice recipes neglecting material
9ead7009 SPIGOT-4677: Add minecraft.admin.command_feedback permission
c3749a23 Remove the Damage tag from items when it is 0.
f74c7b95 SPIGOT-4706: Can't interact with active item
494eef45 Mention requirement of JIRA ticket for bug fixes
51d62dec SPIGOT-4702: Exception when middle clicking certain slots
be557e69 SPIGOT-4700: Add PlayerFishEvent.State.REEL_IN