Add testing config for MetricsServiceUrl study.

Add testing config for MetricsServiceUrl study.

Also removes obsolete config for
UMA_EnableCellularLogUpload.

BUG=none

Review-Url: https://codereview.chromium.org/2860103002
Cr-Commit-Position: refs/heads/master@{#469367}
Committed: https://chromium.googlesource.com/chromium/src/+/d9c705db92238916a6c88e4dca9acb005b2657da

[Alexei Svitkine (slow), 2017-05-04 15:28:10]

asvitkine@chromium.org changed reviewers:
+ jwd@chromium.org

[jwd, 2017-05-04 15:41:44]

lgtm

[Alexei Svitkine (slow), 2017-05-04 16:03:41]

The CQ bit was checked by asvitkine@chromium.org

[commit-bot: I haz the power, 2017-05-04 16:03:57]

CQ is trying da patch.

Follow status at:
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2017-05-04 17:11:48]

CQ is committing da patch.

Bot data: {"patchset_id": 1, "attempt_start_ts": 1493913821735680, "parent_rev":
"ad1d34a88e2b76f24ea00ab18840025897181c6f", "commit_rev":
"d9c705db92238916a6c88e4dca9acb005b2657da"}

[commit-bot: I haz the power, 2017-05-04 17:12:33]

Description was changed from

==========
Add testing config for MetricsServiceUrl study.

Also removes obsolete config for
UMA_EnableCellularLogUpload.

BUG=none
==========

to

==========
Add testing config for MetricsServiceUrl study.

Also removes obsolete config for
UMA_EnableCellularLogUpload.

BUG=none

Review-Url: https://codereview.chromium.org/2860103002
Cr-Commit-Position: refs/heads/master@{#469367}
Committed:
https://chromium.googlesource.com/chromium/src/+/d9c705db92238916a6c88e4dca9a...
==========

[commit-bot: I haz the power, 2017-05-04 17:12:34]

Committed patchset #1 (id:1) as
https://chromium.googlesource.com/chromium/src/+/d9c705db92238916a6c88e4dca9a...