RFR: JDK-8163991: Fix license and copyright headers under test/jdk/javadoc/ and test/tools/javac/

[Iris Clark]

Hi, Sandeep.

> Bug: https://bugs.openjdk.java.net/browse/JDK-8163991
> Webrev: http://cr.openjdk.java.net/~shurailine/8163991/webrev.00/langtools.patch

These changes all look reasonable to me.

Thanks,
Iris