[CSS Grid Layout] Prevent issues with checkLayout() in grid items

[CSS Grid Layout] Prevent issues with checkLayout() in grid items

When we use checkLayout() on a grid item, the results (PASS or FAIL
messages) are added as new auto-placed items in the grid. This causes
that the grid is marked as dirty which could hide bugs in the tests.

Modify the related layout tests to use a different container for the
test results. Updated expectations accordingly.

There is one test missing
"grid-item-addition-auto-placement-update.html". Which will be modified
in the patch to fix the bug in RenderGrid::addChild() (see
https://codereview.chromium.org/198703004/).

Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=169777

[Julien - ping for review, 2014-03-21 18:02:45]

lgtm

[commit-bot: I haz the power, 2014-03-21 18:02:55]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/rego@igalia.com/208133003/1

[commit-bot: I haz the power, 2014-03-21 18:56:02]

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

[commit-bot: I haz the power, 2014-03-21 18:56:02]

Try jobs failed on following builders:
  tryserver.blink on win_blink_rel

[Julien - ping for review, 2014-03-21 19:26:19]

The CQ bit was checked by jchaffraix@chromium.org

[commit-bot: I haz the power, 2014-03-21 19:26:23]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/rego@igalia.com/208133003/1

[commit-bot: I haz the power, 2014-03-21 19:28:38]

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

[commit-bot: I haz the power, 2014-03-21 19:28:39]

Try jobs failed on following builders:
  tryserver.blink on win_blink_rel

[Manuel Rego, 2014-03-21 22:34:41]

The CQ bit was checked by rego@igalia.com

[commit-bot: I haz the power, 2014-03-21 22:34:54]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/rego@igalia.com/208133003/1

[commit-bot: I haz the power, 2014-03-22 04:14:22]

Change committed as 169777