8076543: Add @modules as needed to the langtools tests
Reviewed-by: jjg, shurailine

8062348: langtools tests should close file manager (group 1)
Reviewed-by: darcy

8033414: javac Plugin to receive notification (before and) after the compilation.
Summary: Introducing TaskEvent.Kind.COMPILATION, sending this event before and after compilation.
Reviewed-by: jjg, jfranck
Contributed-by: joel.franck@oracle.com, jan.lahoda@oracle.com

7093891: support multiple task listeners
Reviewed-by: darcy, mcimadamore