This PR proposes to reduce the visibility for constructor and methods in `java.io.SerialCallbackContext`.
------------- Commit messages: - Reduce visibility in j.i.SerialCallbackConext Changes: https://git.openjdk.org/jdk/pull/12143/files Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=12143&range=00 Issue: https://bugs.openjdk.org/browse/JDK-8300868 Stats: 7 lines in 1 file changed: 0 ins; 0 del; 7 mod Patch: https://git.openjdk.org/jdk/pull/12143.diff Fetch: git fetch https://git.openjdk.org/jdk pull/12143/head:pull/12143 PR: https://git.openjdk.org/jdk/pull/12143
