[devil] Don't attempt to remove nothing when removing system apps.

[devil] Don't attempt to remove nothing when removing system apps.

BUG=chromium:710055
Review-Url: https://codereview.chromium.org/2807983004
Committed: https://chromium.googlesource.com/external/github.com/catapult-project/catapult/+/3f05899d417d05db46fafb1f6b5bf869be431daa

[jbudorick, 2017-04-10 22:09:56]

jbudorick@chromium.org changed reviewers:
+ mikecase@chromium.org, rnephew@chromium.org

[mikecase (-- gone --), 2017-04-10 22:23:57]

lgtm

[jbudorick, 2017-04-10 22:24:54]

The CQ bit was checked by jbudorick@chromium.org

[commit-bot: I haz the power, 2017-04-10 22:25:01]

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

[rnephew (Reviews Here), 2017-04-10 22:26:31]

lgtm

[commit-bot: I haz the power, 2017-04-10 22:48:59]

CQ is committing da patch.

Bot data: {"patchset_id": 1, "attempt_start_ts": 1491863094617870, "parent_rev":
"494b9b28a842e03952dc79d686d1307974f813a5", "commit_rev":
"3f05899d417d05db46fafb1f6b5bf869be431daa"}

[commit-bot: I haz the power, 2017-04-10 22:49:04]

Description was changed from

==========
[devil] Don't attempt to remove nothing when removing system apps.

BUG=chromium:710055
==========

to

==========
[devil] Don't attempt to remove nothing when removing system apps.

BUG=chromium:710055

Review-Url: https://codereview.chromium.org/2807983004
Committed:
https://chromium.googlesource.com/external/github.com/catapult-project/catapu...
==========

[commit-bot: I haz the power, 2017-04-10 22:49:05]

Committed patchset #1 (id:1) as
https://chromium.googlesource.com/external/github.com/catapult-project/catapu...