Add noiser and bucketer library

The code to hook this up to reporting will come in subsequent CLs.

As described in [0] and [1]

[0] https://github.com/WICG/turtledove/pull/481

[1]
https://docs.google.com/spreadsheets/d/1cMvX6zHfrN7a52jVrDYDGtCSd3S1TVkjc-cu-yUz2YY/edit#gid=435540624

Bug: 1424406
Change-Id: I477315a4a6f720d2b03e45f19e191173be8c401a
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4335211


Reviewed-by: Maks Orlovich <morlovich@chromium.org>
Commit-Queue: Caleb Raitto <caraitto@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1120052}