With baseline code flushing we also need to hold baseline
data in IsCompiledScope. IsCompiledScope is used in places where we
don't want bytecode / baseline code to be flushed.

Change-Id: I692cdc5fc433dedeabcfc412d9f96d76148ddbe3
BUG: v8:12009
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3048172
Commit-Queue: Mythri Alle <mythria@chromium.org>
Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Cr-Commit-Position: refs/heads/master@{#75903}