The trace_event_common.h header file isn't used with Perfetto any
longer, so avoid adding a dependency to it from cppgc. Additionally
v8_tracing should be a public dependency so that any public headers
exposed from the target can also include tracing-related headers.

Bug: chromium:1006541
Change-Id: Ia3d48a8dad83df2ff3ea1ce36344dbb70ea83709
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2797278
Commit-Queue: Sami Kyöstilä <skyostil@chromium.org>
Commit-Queue: Dan Elphick <delphick@chromium.org>
Auto-Submit: Sami Kyöstilä <skyostil@chromium.org>
Reviewed-by: Dan Elphick <delphick@chromium.org>
Cr-Commit-Position: refs/heads/master@{#73748}