Introduce a flush_baseline_code flag to control if baseline code is
flushed or not. Currently flush_baseline_code implies flush_bytecode
as well. So if flush_baseline_code is enabled both bytecode and baseline
code are flushed. If the flag is disabled we only flush bytecode and
not baseline code.

In a follow-up CL we will add support to control baseline and bytecode
flushing independently i.e. we can flush only bytecode / only baseline
code / both.

Bug: v8:11947
Change-Id: I5a90ed38469de64ed1d736d1eaaeabc2985f0783
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3059684
Commit-Queue: Mythri Alle <mythria@chromium.org>
Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: Omer Katz <omerkatz@chromium.org>
Cr-Commit-Position: refs/heads/master@{#76003}