Perfetto has a mechanism for getting trace data from buffers held alive
by TraceWriters. We enable this with the SetSMBScrapingEnabled() call.

This means we don't need to delete TraceWriter objects and can just leak
them for now, and eventually use thread-local destructors to ensure they
are eventually deleted on thread exit.

Cq-Include-Trybots: luci.v8.try:v8_linux64_perfetto_dbg_ng
Bug: v8:8339
Change-Id: I690bc435c48db6d91eab2fbc7a49ec9feae3b45a
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1607653
Commit-Queue: Peter Marshall <petermarshall@chromium.org>
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Cr-Commit-Position: refs/heads/master@{#61575}