This patch adds a singleton that tracks recently freed code range
regions and provides hints for newly created code ranges such that
the freed addresses are reused.

This is a workaround for the CFG leak described in the linked bug.

Bug: chromium:870054

Change-Id: Ice237a056268379f0fef40abdb1accad125a56b3
Reviewed-on: https://chromium-review.googlesource.com/1174837
Commit-Queue: Ulan Degenbaev <ulan@chromium.org>
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Cr-Commit-Position: refs/heads/master@{#55139}