[MC-58766] ConcurrentModificationException after a huge TNT explosion

I summoned some PrimedTnt, it hogged the CPU and RAM for a few minutes, and then crashed with ConcurrentModificationException.

Steps to reproduce... not sure.
This could do it, but it doesn't happen always.
In regular world with lots of cave mobs.

Something like this coul do it.

/execute @e ~ ~ ~ /summon Chicken ~ ~+50 ~
/execute @e ~ ~ ~ /summon Cow
/execute @e ~ ~ ~ /summon PrimedTnt

Description: Updating screen events

java.util.ConcurrentModificationException
	at java.util.HashMap$HashIterator.nextEntry(HashMap.java:922)
	at java.util.HashMap$KeyIterator.next(HashMap.java:956)
	at oo.b(SourceFile:143)
	at oq.b(SourceFile:38)
	at alu.b(SourceFile:916)
	at ou.b(SourceFile:735)
	at alu.e(SourceFile:931)
	at qh.e(SourceFile:301)
	at coe.s(SourceFile:297)
	at blj.a(SourceFile:1831)
	at blj.a(SourceFile:1819)
	at bpe.a(SourceFile:45)