Address some ClassFile API problems: 1. Missing symbolic representation of LoadableDescriptors, throws spec fixes 2. Fallback to regular parsing for older preview for AccessFlagsImpl 3. ClassRemapperImpl and RebuildingTransformation
--------- - [x] I confirm that I make this contribution in accordance with the [OpenJDK Interim AI Policy](https://openjdk.org/legal/ai). ------------- Commit messages: - ClassFile API review remarks Changes: https://git.openjdk.org/valhalla/pull/2557/files Webrev: https://webrevs.openjdk.org/?repo=valhalla&pr=2557&range=00 Issue: https://bugs.openjdk.org/browse/JDK-8386791 Stats: 42 lines in 5 files changed: 35 ins; 0 del; 7 mod Patch: https://git.openjdk.org/valhalla/pull/2557.diff Fetch: git fetch https://git.openjdk.org/valhalla.git pull/2557/head:pull/2557 PR: https://git.openjdk.org/valhalla/pull/2557
