Use rowgroup and columgroup properties to expose table headers.

Use rowgroup and columgroup properties to expose table headers.

Update current implementation so that rowgroup and columngroup
properties are used when exposing table headers.

BUG=448042, 435081
Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=188370

[k.czech, 2015-01-12 15:42:59]

k.czech@samsung.com changed reviewers:
+ dmazzoni@chromium.org

[dmazzoni, 2015-01-13 22:41:31]

The CQ bit was checked by dmazzoni@chromium.org

[dmazzoni, 2015-01-13 22:41:31]

lgtm

[commit-bot: I haz the power, 2015-01-13 22:42:08]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/846013002/40001

[commit-bot: I haz the power, 2015-01-14 00:54:00]

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

[commit-bot: I haz the power, 2015-01-14 00:54:01]

Try jobs failed on following builders:
  win_blink_rel on tryserver.blink
(http://build.chromium.org/p/tryserver.blink/builders/win_blink_rel/builds/46050)

[k.czech, 2015-01-14 09:02:15]

The CQ bit was checked by k.czech@samsung.com

[commit-bot: I haz the power, 2015-01-14 09:02:41]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/846013002/40001

[commit-bot: I haz the power, 2015-01-14 09:45:43]

Committed patchset #3 (id:40001) as
https://src.chromium.org/viewvc/blink?view=rev&revision=188370