Almost everywhere, we use the ProcessedFeedback abstraction to
query feedback in the compiler. The remaining exception is in handling
RegExp, Object and Array literals. By bringing this in line with
other feedback queries, we no longer need to serialize all feedback
vector slots (possibly wasteful of memory), and offer a uniform way
to pick up feedback everywhere.

Bug: v8:7790, v8:9396
Change-Id: Ice42587595fe30bebfbd7835d2b2e9e49601c92e
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1807358
Commit-Queue: Michael Stanton <mvstanton@chromium.org>
Reviewed-by: Georg Neis <neis@chromium.org>
Reviewed-by: Maya Lekova <mslekova@chromium.org>
Cr-Commit-Position: refs/heads/master@{#64016}