The {AddOutOfLineTrap} method shows up with several percent of runtime
in performance profiles. The majority of that was spent copying entries
when growing the underlying vector.
Pre-reserving space in that vector removes most of that overhead.

R=thibaudm@chromium.org

Change-Id: I1befb75b070d4f803770c2afcc5c82ffb9bfb522
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3688511Reviewed-by: Thibaud Michaud <thibaudm@chromium.org>
Commit-Queue: Clemens Backes <clemensb@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80943}