Add user-agent flag to headless

Add user-agent flag to headless

BUG=604324
Review-Url: https://codereview.chromium.org/2805793003
Cr-Commit-Position: refs/heads/master@{#463221}
Committed: https://chromium.googlesource.com/chromium/src/+/6de4c9216f701b9e0e075bff999350853a9c5a74

[irisu, 2017-04-07 06:05:14]

irisu@chromium.org changed reviewers:
+ skyostil@chromium.org

[Sami, 2017-04-07 09:44:15]

lgtm, thanks! Sorry for the back-and-forth about this.

[irisu, 2017-04-10 00:59:14]

The CQ bit was checked by irisu@chromium.org

[commit-bot: I haz the power, 2017-04-10 00:59:22]

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, 2017-04-10 01:11:57]

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

[commit-bot: I haz the power, 2017-04-10 01:11:58]

Try jobs failed on following builders:
  linux_chromium_compile_dbg_ng on master.tryserver.chromium.linux (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...)

[irisu, 2017-04-10 02:28:49]

On 2017/04/10 01:11:58, commit-bot: I haz the power wrote:
> Try jobs failed on following builders:
>   linux_chromium_compile_dbg_ng on master.tryserver.chromium.linux
(JOB_FAILED,
>
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...)

Had to add headless_shell_switches to build rule for headless_lib, PTAL.

[Sami, 2017-04-10 10:19:52]

Still lgtm.

[Sami, 2017-04-10 10:20:35]

The CQ bit was checked by skyostil@chromium.org

[commit-bot: I haz the power, 2017-04-10 10:20:46]

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, 2017-04-10 11:28:49]

CQ is committing da patch.

Bot data: {"patchset_id": 20001, "attempt_start_ts": 1491819635703670,
"parent_rev": "09d1b60e7c9facda095d609e8b2a256caeec105f", "commit_rev":
"6de4c9216f701b9e0e075bff999350853a9c5a74"}

[commit-bot: I haz the power, 2017-04-10 11:29:40]

Description was changed from

==========
Add user-agent flag to headless

BUG=604324
==========

to

==========
Add user-agent flag to headless

BUG=604324

Review-Url: https://codereview.chromium.org/2805793003
Cr-Commit-Position: refs/heads/master@{#463221}
Committed:
https://chromium.googlesource.com/chromium/src/+/6de4c9216f701b9e0e075bff9993...
==========

[commit-bot: I haz the power, 2017-04-10 11:29:41]

Committed patchset #2 (id:20001) as
https://chromium.googlesource.com/chromium/src/+/6de4c9216f701b9e0e075bff9993...