W3C auto test import CL.

W3C auto test import CL.

TBR=qyearsley@chromium.org

[blink-w3c-test-autoroller, 2016-09-13 20:14:30]

'Modifies TestExpectations and/or downloads new baselines for tests'

[blink-w3c-test-autoroller, 2016-09-13 20:14:32]

The CQ bit was checked by blink-w3c-test-autoroller@chromium.org

[commit-bot: I haz the power, 2016-09-13 20:15:00]

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, 2016-09-13 21:32:43]

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

[commit-bot: I haz the power, 2016-09-13 21:32:44]

Try jobs failed on following builders:
  mac_chromium_rel_ng on master.tryserver.chromium.mac (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.mac/builders/mac_chromium_rel_...)

[qyearsley, 2016-09-14 17:23:52]

On 2016/09/13 at 21:32:44, commit-bot wrote:
> Try jobs failed on following builders:
>   mac_chromium_rel_ng on master.tryserver.chromium.mac (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.mac/builders/mac_chromium_rel_...)

update-w3c-test-expectations added a blank line to TestExpectations and failed
to download the baseline for origin-of-data-document.html. Not currently sure
why this is; update-w3c-test-expectations should have better logging.

[qyearsley, 2016-09-14 18:39:47]

On 2016/09/14 at 17:23:52, qyearsley wrote:
> On 2016/09/13 at 21:32:44, commit-bot wrote:
> > Try jobs failed on following builders:
> >   mac_chromium_rel_ng on master.tryserver.chromium.mac (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.mac/builders/mac_chromium_rel_...)
> 
> update-w3c-test-expectations added a blank line to TestExpectations and failed
to download the baseline for origin-of-data-document.html. Not currently sure
why this is; update-w3c-test-expectations should have better logging.

I think there are two bugs that prevented this from working correctly:
 1. After running rebaseline-cl to download new baselines, baselines for new
tests are still "untracked" and won't be committed and uploaded. Ideally we want
to stage all changes ready to commit (see http://crbug.com/639410).
 2. When there are no new TestExpectation lines to add and the marker line
exists in TestExpectations, a blank line is added although it shouldn't be. A
unit test should be added and this should be fixed.