hg: kulla/dev/langtools: Remove classes that are no longer used.

[robert.field at oracle.com]

Changeset: 5dcdb23b558b
Author:    rfield
Date:      2015-05-20 09:41 -0700
URL:       http://hg.openjdk.java.net/kulla/dev/langtools/rev/5dcdb23b558b

Remove classes that are no longer used.

- src/jdk.jshell/share/classes/jdk/internal/jshell/impl/CountingStringReader.java
! src/jdk.jshell/share/classes/jdk/internal/jshell/impl/JDIEventHandler.java
- src/jdk.jshell/share/classes/jdk/internal/jshell/impl/ThreadInfo.java
- src/jdk.jshell/share/classes/jdk/internal/jshell/impl/TreeElementScanner.java