This CL adds an argument to the heap profiler that allows to control
whether global objects (e.g. 'window' in JavaScript) are treated as
roots in the heap snapshot. Doing so hides blink-internal details and
is often a good choice when user-JS leaks are investigated. Sometimes,
however, this introduces spurious retainer cycles, which are hard to
debug.

Previously, this option was exposed as a V8 flag. The blink
implications of the build-time V8 flag are now available via
the new blink flag `enable_additional_blink_object_names`.

Tbr: hpayer@chromium.org
Bug: chromium:1034504
Change-Id: Ibe9412917ae598a3ff0c3dc956ab0bc179f50a21
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1967387Reviewed-by: Sigurd Schneider <sigurds@chromium.org>
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Commit-Queue: Sigurd Schneider <sigurds@chromium.org>
Cr-Commit-Position: refs/heads/master@{#65491}