OOR-CORS: deprecate metrics

Since we finished analyzing memory impact and cache performance,
we will deprecate Net.Cors.* metrics as we originally planned.

Bug: 975268
Change-Id: I7922d6f80135099c277a0e1e6277405e903ee967
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1670731
Reviewed-by: Yutaka Hirano <yhirano@chromium.org>
Reviewed-by: Jesse Doherty <jwd@chromium.org>
Commit-Queue: Jesse Doherty <jwd@chromium.org>
Auto-Submit: Takashi Toyoshima <toyoshim@chromium.org>
Cr-Commit-Position: refs/heads/master@{#672260}
13 files changed