There's another bug in ClassFile transform composition where the downstream transform receives items from upstream transform's chained builders before the downstream transform itself starts. This is a simple fix, and a test case against `ClassTransform` is added.
------------- Commit messages: - 8336588: Ensure Transform downstream receives upstream start items only after downstream started Changes: https://git.openjdk.org/jdk/pull/20227/files Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=20227&range=00 Issue: https://bugs.openjdk.org/browse/JDK-8336588 Stats: 63 lines in 2 files changed: 49 ins; 9 del; 5 mod Patch: https://git.openjdk.org/jdk/pull/20227.diff Fetch: git fetch https://git.openjdk.org/jdk.git pull/20227/head:pull/20227 PR: https://git.openjdk.org/jdk/pull/20227
