[MC-152368] Book editing after hitting "Done" crashes game in servers.

Replication:

Write something in a book

Hit "Done"

Open Book Again

Type

Crash

Expected: Show the letter I typed

Actual: Game Crashes after a couple of seconds

1.14.1: crash-2019-05-19_10.10.19-client.txt

Description: keyPressed event handler

java.lang.StringIndexOutOfBoundsException: String index out of range: 73
	at java.lang.AbstractStringBuilder.deleteCharAt(Unknown Source)
	at java.lang.StringBuilder.deleteCharAt(Unknown Source)
	at das.b(SourceFile:322)
	at das.b(SourceFile:278)
	at das.keyPressed(SourceFile:229)
	at cvi.a(SourceFile:410)
	at czt.wrapScreenError(SourceFile:441)
	at cvi.a(SourceFile:408)
	at org.lwjgl.glfw.GLFWKeyCallbackI.callback(GLFWKeyCallbackI.java:37)
	at org.lwjgl.system.JNI.invokeV(Native Method)
	at org.lwjgl.glfw.GLFW.glfwPollEvents(GLFW.java:3050)
	at cud.l(SourceFile:425)
	at cud.c(SourceFile:283)
	at cvk.b(SourceFile:1023)
	at cvk.e(SourceFile:976)
	at cvk.b(SourceFile:411)
	at net.minecraft.client.main.Main.main(SourceFile:154)