Support of specify local prebuilt network service file.

Support of specify local prebuilt network service file.

This change is chromium part of
https://codereview.chromium.org/921053003/

And out-of-date TODO is removed as well.

TEST=
BUG=458409
Committed: https://crrev.com/176dd4a94f2fbea1d0962888b3f62bdc21e76cd7
Cr-Commit-Position: refs/heads/master@{#319783}

[haltonhuo, 2015-03-06 15:32:31]

halton.huo@intel.com changed reviewers:
+ blundell@chromium.org, cjhopman@chromium.org

[haltonhuo, 2015-03-06 15:32:32]

blundell, as we discussed in https://codereview.chromium.org/921053003/, this CL
is uploaded for chromium part. Please review.

[haltonhuo, 2015-03-09 12:21:19]

halton.huo@intel.com changed reviewers:
+ qsr@chromium.org

[haltonhuo, 2015-03-09 12:21:19]

qsr, as you suggested in https://codereview.chromium.org/921053003/, I renamed
the var as prebuilt_network_service_location

[qsr, 2015-03-09 13:10:23]

lgtm

[haltonhuo, 2015-03-09 13:32:15]

On 2015/03/09 13:10:23, qsr wrote:
> lgtm

Thanks for review. cjhopman, could you give your lgtm so that I can check the
commit box?

[cjhopman, 2015-03-09 17:13:05]

lgtm

[haltonhuo, 2015-03-09 23:12:09]

The CQ bit was checked by halton.huo@intel.com

[commit-bot: I haz the power, 2015-03-09 23:13:32]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/983143003/20001

[commit-bot: I haz the power, 2015-03-10 00:03:58]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2015-03-10 00:04:41]

Patchset 2 (id:??) landed as
https://crrev.com/176dd4a94f2fbea1d0962888b3f62bdc21e76cd7
Cr-Commit-Position: refs/heads/master@{#319783}