GitLab

This CL reduces the memory associated by a ScopeLock:
- Remove ScopeLock::is_locked_: We can check if the release callback
  is nullptr to know if the lock is held.
- Remove level and ScopedLockRange bound to the release callback:
  The values are already stored in the ScopeLock and can passed when
  invoking the callback.

The goal is to offset the memory that will be used in a subsequent CL
to track the frame holding each ScopeLock.

Bug: 980533
Change-Id: I9b6852db43c2000ae1b68c31996921bc52a63916
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1838374
Commit-Queue: François Doray <fdoray@chromium.org>
Reviewed-by: Daniel Murphy <dmurph@chromium.org>
Cr-Commit-Position: refs/heads/master@{#703391}