The following histograms have been deprecated, as they are superseded
by V8.GC.Cycle.*.Young or not needed anymore (next to each, the
corresponding isolate counter):

- V8.GCScavenger (gc_scavenger)
- V8.GCScavengerBackground (gc_scavenger_background)
- V8.GCScavengeReason (scavenge_reason)
- V8.GCScavengerForeground (gc_scavenger_foreground)
- V8.GCBackgroundScavenger (background_scavenger)
- V8.GCMarkCompactor (gc_mark_compactor)

This CL removes the corresponding instrumentation in the code and the
isolate counters.

Bug: chromium:1154636
Bug: chromium:1299555
Change-Id: I62d28ff60ef47a058fe148c7855af8e2c1cc0aed
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3487548Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Commit-Queue: Nikolaos Papaspyrou <nikolaos@chromium.org>
Cr-Commit-Position: refs/heads/main@{#79308}