Similar to NativeRegExpMacroAssembler::Result, the regexp interpreter
will need a RETRY return code in case the subject string
representation changes during an interrupt. This CL adds a new
IrregexpInterpreter::Result type to decouple from RegExpImpl::Result.

Bug: v8:8724
Change-Id: I946fc0cbc4d7d8631312b72f13a45abeb9986905
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1511472Reviewed-by: Peter Marshall <petermarshall@chromium.org>
Commit-Queue: Jakob Gruber <jgruber@chromium.org>
Cr-Commit-Position: refs/heads/master@{#60154}