This is the final part of the tier-up commit series. It implements:

- A prologue in NCI code objects that checks and acts upon the
optimization marker.
- Currently, handling is deferred to the InterpreterEntryTrampoline
but this will change in the future.
- The lifecycle is otherwise like Ignition-to-Turbofan; the runtime
profiler marks a function for optimization, the next call to that
function triggers optimization by calling into runtime, and the
finished code object is installed both on the JSFunction and the
optimized code cache.
- The feedback vector's kOptimizedCodeWeakOrSmiOffset slot is
currently reused for the mid-to-top tier up.

Cq-Include-Trybots: luci.v8.try:v8_linux64_fyi_rel_ng
Bug: v8:8888
Change-Id: Iff50b05ddcc68b25d7ed0f1e0d20af076a1522a0
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2361466Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
Reviewed-by: Mythri Alle <mythria@chromium.org>
Commit-Queue: Jakob Gruber <jgruber@chromium.org>
Cr-Commit-Position: refs/heads/master@{#69808}