RFR 11 (S): 8195069: LogCompilation - add basic unit tests

[Eric Caspole]

Hi everybody,
Could I have reviews for this change which adds very simple junits and 
more importantly the structure to add better ones later, to help prevent 
bit rot in LogCompilation.

JBS: https://bugs.openjdk.java.net/browse/JDK-8195069

Webrev: http://cr.openjdk.java.net/~ecaspole/JDK-8195069/webrev/

Thanks,
Eric