This reverts commit 9c7f6c25.

Reason for revert:
Not working
https://logs.chromium.org/logs/infra-internal/buildbucket/cr-buildbucket.appspot.com/8858807889610091152/+/steps/franky/0/steps/git_cl_upload/0/stdout

Original change's description:
> [owners] Refactor OwnersClient.
>
> - Remove GetChangeApprovalStatus and GetFilesApprovalStatus.
> - Make host, project and branch part of GerritClient.
> - Rename ListOwnersForFile to ListOwners.
>
> Change-Id: I1f610a64f0217ce54e5ce4a210026535adc1c2e5
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/tools/depot_tools/+/2587268
> Commit-Queue: Edward Lesmes <ehmaldonado@chromium.org>
> Reviewed-by: Gavin Mak <gavinmak@google.com>

TBR=ehmaldonado@chromium.org,gavinmak@google.com,infra-scoped@luci-project-accounts.iam.gserviceaccount.com,sokcevic@google.com

# Not skipping CQ checks because original CL landed > 1 day ago.

Change-Id: I4928df90856526210a4fd4d104e6cc96aa005bc2
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/tools/depot_tools/+/2613925
Commit-Queue: Edward Lesmes <ehmaldonado@chromium.org>
Reviewed-by: Stephen Martinis <martiniss@chromium.org>
Reviewed-by: Edward Lesmes <ehmaldonado@chromium.org>