The backtracking stack (which is actually a generic stack) used to be
statically sized. At 10k elements, it was fairly large, but still easy
to overflow on large subject strings. This CL changes it to a
std::vector-based implementation instead which grows on-demand.

Drive-by: Add braces to the BYTECODE cases to make clang-format
produce a nicer output.

Bug: v8:8776
Change-Id: If41a444fe3d05f6d5be1be019129788a86e6118b
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1634914Reviewed-by: Peter Marshall <petermarshall@chromium.org>
Commit-Queue: Jakob Gruber <jgruber@chromium.org>
Cr-Commit-Position: refs/heads/master@{#61912}