/tellraw does not work

The bug

The fix for MC-121695 means that /tellraw can no longer be used for a single target. /tellraw used on @p or on @a (in singleplayer) is parsed but execution fails with the following error:

17w45b

java.lang.IllegalArgumentException: No such argument 'target' exists on this command
	at com.mojang.brigadier.context.CommandContext.getArgument(CommandContext.java:44) ~[brigadier-0.1.8.jar:?]
	at bp.e(SourceFile:73) ~[17w45b.jar:?]
	at or.a(SourceFile:27) ~[17w45b.jar:?]
	at com.mojang.brigadier.CommandDispatcher.execute(CommandDispatcher.java:117) ~[brigadier-0.1.8.jar:?]
	at com.mojang.brigadier.CommandDispatcher.execute(CommandDispatcher.java:74) ~[brigadier-0.1.8.jar:?]
	at bl.a(SourceFile:169) [17w45b.jar:?]
	at qg.c(SourceFile:851) [17w45b.jar:?]
	at qg.a(SourceFile:838) [17w45b.jar:?]
	at jt.a(SourceFile:37) [17w45b.jar:?]
	at jt.a(SourceFile:9) [17w45b.jar:?]
	at go$1.run(SourceFile:13) [17w45b.jar:?]
	at java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source) [?:1.8.0_151]
	at java.util.concurrent.FutureTask.run(Unknown Source) [?:1.8.0_151]
	at h.a(SourceFile:121) [17w45b.jar:?]
	at net.minecraft.server.MinecraftServer.w(SourceFile:628) [17w45b.jar:?]
	at net.minecraft.server.MinecraftServer.v(SourceFile:584) [17w45b.jar:?]
	at cjf.v(SourceFile:149) [17w45b.jar:?]
	at net.minecraft.server.MinecraftServer.run(SourceFile:489) [17w45b.jar:?]
	at java.lang.Thread.run(Unknown Source) [?:1.8.0_151]