8076543: Add @modules as needed to the langtools testsReviewed-by: jjg, shurailine
8005282: Use @library tag with non-relative path for javac testsReviewed-by: jjg
6983738: Use a JavacTestingAbstractProcessorReviewed-by: jjg
6403456: -Werror should work with annotation processingReviewed-by: darcy