[ios] Safely handle non-existent plists in OmniboxGeolocationConfig.

[ios] Safely handle non-existent plists in OmniboxGeolocationConfig.

This CL adds an early return rather than DCHECKing when the plist is missing.

BUG=666375
Committed: https://crrev.com/2f4aa595a1e6d9ba2c93916fb3f79a8adf0c18e4
Cr-Commit-Position: refs/heads/master@{#438719}

[rohitrao (ping after 24h), 2016-12-06 02:21:25]

The CQ bit was checked by rohitrao@chromium.org to run a CQ dry run

[commit-bot: I haz the power, 2016-12-06 02:21:59]

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

[rohitrao (ping after 24h), 2016-12-06 02:22:00]

rohitrao@chromium.org changed reviewers:
+ pkl@chromium.org

[rohitrao (ping after 24h), 2016-12-06 02:22:01]

If a plist exists, it must have at least one valid domain, but if there is no
plist at all, that's fine.

[commit-bot: I haz the power, 2016-12-06 02:33:09]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2016-12-06 02:33:10]

Dry run: This issue passed the CQ dry run.

[rohitrao (ping after 24h), 2016-12-12 15:32:35]

Please take a look.

[pkl (ping after 24h if needed), 2016-12-15 02:22:55]

LGTM.

[rohitrao (ping after 24h), 2016-12-15 02:24:16]

Per discussion, I'm adding comments explaining that:
- the early return is for when the plist is missing entirely (which is expected
in chromium builds)
- the DCHECK is for when a plist is present, but contains unexpected data (which
should never happen -- if we wanted no eligible domains, we'd just delete the
plist)

[rohitrao (ping after 24h), 2016-12-15 02:43:42]

The CQ bit was checked by rohitrao@chromium.org

[rohitrao (ping after 24h), 2016-12-15 02:43:42]

The patchset sent to the CQ was uploaded after l-g-t-m from pkl@chromium.org
Link to the patchset: https://codereview.chromium.org/2551423002/#ps20001
(title: "Add comments.")

[commit-bot: I haz the power, 2016-12-15 02:43:53]

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, 2016-12-15 02:53:27]

CQ is committing da patch.

Bot data: {"patchset_id": 20001, "attempt_start_ts": 1481769822231590,
"parent_rev": "7d6d2d6a4fa0f7f4b05eca55606e64417aecb98d", "commit_rev":
"11b3a54d7e72fcc8405a114e2b3b3c6aa4a218ca"}

[commit-bot: I haz the power, 2016-12-15 02:53:50]

Description was changed from

==========
[ios] Safely handle non-existent plists in OmniboxGeolocationConfig.

This CL adds an early return rather than DCHECKing when the plist is missing.

BUG=666375
==========

to

==========
[ios] Safely handle non-existent plists in OmniboxGeolocationConfig.

This CL adds an early return rather than DCHECKing when the plist is missing.

BUG=666375

Review-Url: https://codereview.chromium.org/2551423002
==========

[commit-bot: I haz the power, 2016-12-15 02:53:51]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2016-12-15 02:58:16]

Description was changed from

==========
[ios] Safely handle non-existent plists in OmniboxGeolocationConfig.

This CL adds an early return rather than DCHECKing when the plist is missing.

BUG=666375

Review-Url: https://codereview.chromium.org/2551423002
==========

to

==========
[ios] Safely handle non-existent plists in OmniboxGeolocationConfig.

This CL adds an early return rather than DCHECKing when the plist is missing.

BUG=666375

Committed: https://crrev.com/2f4aa595a1e6d9ba2c93916fb3f79a8adf0c18e4
Cr-Commit-Position: refs/heads/master@{#438719}
==========

[commit-bot: I haz the power, 2016-12-15 02:58:17]

Patchset 2 (id:??) landed as
https://crrev.com/2f4aa595a1e6d9ba2c93916fb3f79a8adf0c18e4
Cr-Commit-Position: refs/heads/master@{#438719}