[tsmon] Add root_labels into MetricsCollection

Please find the bug description and go/ts-mon-custom-schema for more details.

Bug: 941883
Change-Id: If5f336ae8dc93382ac91d75147d8ca571bfd21c0
R: junyer
Reviewed-on: https://chromium-review.googlesource.com/c/infra/infra/+/1741508
Commit-Queue: Scott Lee <ddoman@chromium.org>
Reviewed-by: Paul Wankadia <junyer@google.com>
Cr-Original-Commit-Position: refs/heads/master@{#24972}
Cr-Mirrored-From: https://chromium.googlesource.com/infra/infra
Cr-Mirrored-Commit: 16f1639e3fbaf3351fade896b04501bb00ee693d
2 files changed
tree: 332d0d13ce739c0aa08ae933781844d0dde13dbd
  1. .coveragerc
  2. infra_libs/
  3. setup.py