Non-static classes hold a link to their parent classes, which in many cases can be avoided. Similar cleanup in java.base - [JDK-8261880](https://bugs.openjdk.java.net/browse/JDK-8261880)
------------- Commit messages: - [PATCH] Change nested classes in jdk.attach to static nested classes where possible Changes: https://git.openjdk.java.net/jdk/pull/5904/files Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=5904&range=00 Issue: https://bugs.openjdk.java.net/browse/JDK-8275240 Stats: 4 lines in 4 files changed: 0 ins; 0 del; 4 mod Patch: https://git.openjdk.java.net/jdk/pull/5904.diff Fetch: git fetch https://git.openjdk.java.net/jdk pull/5904/head:pull/5904 PR: https://git.openjdk.java.net/jdk/pull/5904
