Crash while teleporting in spectator mode

Steps to reproduce

• Create a creative world with seed -928546829401929186

• /gamemode spectator @a

• /tp -503 48 -1399

Description: Exception generating new chunk

java.util.concurrent.ExecutionException: java.lang.NullPointerException
	at java.util.concurrent.CompletableFuture.get(CompletableFuture.java:2237)
	at sj.c(SourceFile:129)
	at bbd.d(SourceFile:248)
	at bbd.l(SourceFile:243)
	at bbd.b(SourceFile:597)
	at ahz.a(SourceFile:1145)
	at arn.dj(SourceFile:336)
	at arn.R_(SourceFile:278)
	at sm.i(SourceFile:372)
	at tj.Y_(SourceFile:189)
	at hs.a(SourceFile:221)
	at ti.c(SourceFile:175)
	at net.minecraft.server.MinecraftServer.w(SourceFile:720)
	at net.minecraft.server.MinecraftServer.v(SourceFile:627)
	at dhr.v(SourceFile:156)
	at net.minecraft.server.MinecraftServer.run(SourceFile:532)
	at java.lang.Thread.run(Thread.java:745)
Caused by: java.lang.NullPointerException
	at bze.d(SourceFile:121)
	at bze.b(SourceFile:160)
	at bze.c(SourceFile:214)
	at bze.a(SourceFile:32)
	at bze$p.a(SourceFile:312)
	at bze$l.a(SourceFile:507)
	at bvr$a.<init>(SourceFile:83)
	at bvr.a(SourceFile:61)
	at bvs.a(SourceFile:252)
	at bvs.a(SourceFile:80)
	at bxy.a(SourceFile:16)
	at bxy.a(SourceFile:13)
	at brv.a(SourceFile:27)
	at bbx.a(SourceFile:515)
	at bpi.a(SourceFile:109)
	at sy.a(SourceFile:12)
	at sx.a(SourceFile:34)
	at bpm.a(SourceFile:87)
	at td.a(SourceFile:59)
	at td.a(SourceFile:23)
	at agf$a.a(SourceFile:143)
	at agf$a$$Lambda$1359/275188482.apply(Unknown Source)
	at java.util.concurrent.CompletableFuture$AsyncApply.exec(CompletableFuture.java:501)
	at java.util.concurrent.ForkJoinTask.doExec(ForkJoinTask.java:289)
	at java.util.concurrent.ForkJoinPool$WorkQueue.runTask(ForkJoinPool.java:902)
	at java.util.concurrent.ForkJoinPool.scan(ForkJoinPool.java:1689)
	at java.util.concurrent.ForkJoinPool.runWorker(ForkJoinPool.java:1644)
	at java.util.concurrent.ForkJoinWorkerThread.run(ForkJoinWorkerThread.java:157)