RFR: 8365191: Cleanup after removing LockingMode related code [v3]

[Coleen Phillimore]

On Wed, 24 Sep 2025 13:05:23 GMT, Fredrik Bredberg <fbredberg at openjdk.org> wrote:

>> This is a general cleanup after removing `LockingMode` related code.
>> It's a sub-task of [JDK-8344261](https://bugs.openjdk.org/browse/JDK-8344261).
>> It includes:
>> - Removing asserts that are no longer necessary, since we removed legacy locking and monitor locking.
>> - Removing or rewriting comments, arguments or functions that are related to displaced headers.
>> - Remove "always true" parameter from `MonitorExitStub`.
>> - Re-type/name metadata in `BasicLock`.
>> 
>> Tier1-5 passes okay on supported platforms.
>> 
>> All other platforms (arm, ppc, riscv and s390) has been sanity checked using Qemu.
>
> Fredrik Bredberg has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Fixed a mixup

Looks good!

-------------

Marked as reviewed by coleenp (Reviewer).

PR Review: https://git.openjdk.org/jdk/pull/27448#pullrequestreview-3262810994