Premonomorphic state was only used for store globals to handle contextual
store on a global object [1]. We now handle these differently and we
move to fast handlers even without going through premonomorphic state
after this cl: https://chromium-review.googlesource.com/c/v8/v8/+/1807356.
Also, with lazy feedback this would be a relatively uncommon case anyway.
So, we no longer need premonomorphic state. This cl removes this state
entirely.


[1]: https://bugs.chromium.org/p/v8/issues/detail?id=8712


Bug: v8:8394
Change-Id: I71fb918b82b0c321a9705e32c8fc44e9ec223b38
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1833690Reviewed-by: Maya Lekova <mslekova@chromium.org>
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Commit-Queue: Mythri Alle <mythria@chromium.org>
Cr-Commit-Position: refs/heads/master@{#64085}