Re-enable _LIBCPP_ABI_VERSION for Fuchsia

This seems to work now.
https://fuchsia-review.googlesource.com/c/fuchsia/+/1010227
allegedly fixed the Fuchsia SDK, and
https://chromium-review.googlesource.com/c/chromium/src/+/5381851
apparently rolled that in.

Reverts https://chromium-review.googlesource.com/c/chromium/src/+/5347218
(...and adds a define to force a full rebuild).

Bug: 328308661
Change-Id: I1ba63ff3b01cdd77f41a15eecd0061a4027ca5bf
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5387613
Commit-Queue: Hans Wennborg <hans@chromium.org>
Commit-Queue: Nico Weber <thakis@chromium.org>
Auto-Submit: Nico Weber <thakis@chromium.org>
Reviewed-by: Hans Wennborg <hans@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1277632}
NOKEYCHECK=True
GitOrigin-RevId: 90f3edf06d3032cdd702bcacf505055fb838ad44
1 file changed