This CL adds more systematic predicates to JSFunction to reason about
available code kinds. Introduced terminology:

- Attached code kinds are accessible directly from the JSFunction
  itself.
- Available code kinds are either attached or accessible indirectly.
- The Active code kind is the one that would be executed on the next
  function execution.

Bug: v8:8888
Change-Id: I9468884dfe97a6cb73f8329b2b6cb62b622d3e7a
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2345966
Commit-Queue: Jakob Gruber <jgruber@chromium.org>
Auto-Submit: Jakob Gruber <jgruber@chromium.org>
Reviewed-by: Clemens Backes <clemensb@chromium.org>
Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Cr-Commit-Position: refs/heads/master@{#69325}