Previously ScrapeNativeContext was written quite defensively which could result
in false positives and crashes.

This CL makes the function always bail out when we're running on non-ia32/x64
since only those 2 properly verify whether the program is setting up a frame.
If we are setting up a frame, the context will be garbage.

This CL also disables profiler tests when TSAN is running since TSAN makes
ScrapeNativeContext unsafe: it considers SIGPROF asynchronous and will run the
handler after the program has already run further than the context that's
passed into the handler.

Bug: v8:9860, v8:9869
Change-Id: I5a08374feba2e0e77ddd59e02dc2d7e9c90c2e04
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1866469Reviewed-by: Peter Marshall <petermarshall@chromium.org>
Commit-Queue: Toon Verwaest <verwaest@chromium.org>
Auto-Submit: Toon Verwaest <verwaest@chromium.org>
Cr-Commit-Position: refs/heads/master@{#64354}