New candidate JEP: 403: Strongly Encapsulate JDK Internals

[mark.reinhold at oracle.com]

https://openjdk.java.net/jeps/403

  Summary: Strongly encapsulate all internal elements of the JDK, except
  for critical internal APIs such as sun.misc.Unsafe.  It will no longer
  be possible to relax the strong encapsulation of internal elements
  via a single command-line option, as was possible in JDKÂ 9 through
  JDKÂ 16.

- Mark