hg: jdk/sandbox: Remove unused classes

[erik.gahlin at oracle.com]

Changeset: 3efa9b992c4d
Author:    egahlin
Date:      2019-05-24 20:51 +0200
URL:       http://hg.openjdk.java.net/jdk/sandbox/rev/3efa9b992c4d

Remove unused classes

- src/jdk.jfr/share/classes/jdk/jfr/internal/util/PerfectHashMap.java
- src/jdk.jfr/share/classes/jdk/jfr/internal/util/PrimitiveHashMap.java
- src/jdk.jfr/share/classes/jdk/jfr/internal/util/UniversalHashFamily.java