Use bits flag for caseFirst, hourCycle and numeric in Locale.
Also set up macro for V8_INTL_SUPPORT only in heap-symbols.h

Bug: v8:7684, v8:8256
Cq-Include-Trybots: luci.v8.try:v8_linux_noi18n_rel_ng
Change-Id: I3f6956b6dd5782e88676667381a7d8a7b2476bfc
Reviewed-on: https://chromium-review.googlesource.com/c/1262476
Commit-Queue: Frank Tang <ftang@chromium.org>
Reviewed-by: Sathya Gunasekaran <gsathya@chromium.org>
Cr-Commit-Position: refs/heads/master@{#56423}