[CSSGridLayout] <embed> elements leaving stale pointers into grid

[CSSGridLayout] <embed> elements leaving stale pointers into grid

In r177653 (https://codereview.chromium.org/358673003) we added a call to
splitAnonymousBoxesAroundChild() in RenderGrid::addChild() in order to properly
deal with anonymous grid items being added to the grid. The thing is that we
should invalidate the grid after that because that call changes the render tree
(normally creating a new anonymous block which will be the parent of the child).

The changes in the addChild() function in r177258 hid this bug.

    if (!style()->isGridAutoFlowAlgorithmStack()) {
        dirtyGrid();
        return;
    }

Since the default initial value of 'grid-auto-flow' is now 'row', every grid
that does not specify a value for the property enters this block by default. So
the grid was invalidated there hidding the underlying problem. But if we specify
'grid-auto-flow: stack' then we easily reach an inconsistent state in our
internal representation (and hit ASSERTs).

BUG=401479
Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=181339

[svillar, 2014-08-20 16:35:35]

Sending for review.

[cbiesinger, 2014-08-21 21:30:00]

lgtm

[svillar, 2014-08-22 07:25:27]

The CQ bit was checked by svillar@igalia.com

[commit-bot: I haz the power, 2014-08-22 07:25:51]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/svillar@igalia.com/488163002/1

[svillar, 2014-08-22 07:38:15]

The CQ bit was checked by svillar@igalia.com

[commit-bot: I haz the power, 2014-08-22 07:38:17]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/svillar@igalia.com/488163002/1

[commit-bot: I haz the power, 2014-08-22 08:23:38]

FYI, CQ is re-trying this CL (attempt #1).
The failing builders are:
  android_chromium_gn_compile_rel on tryserver.blink
(http://build.chromium.org/p/tryserver.blink/builders/android_chromium_gn_comp...)
  blink_presubmit on tryserver.blink
(http://build.chromium.org/p/tryserver.blink/builders/blink_presubmit/builds/1...)

[commit-bot: I haz the power, 2014-08-22 08:26:23]

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

[commit-bot: I haz the power, 2014-08-22 08:26:24]

Try jobs failed on following builders:
  blink_presubmit on tryserver.blink
(http://build.chromium.org/p/tryserver.blink/builders/blink_presubmit/builds/1...)

[svillar, 2014-08-22 14:03:35]

On 2014/08/22 08:26:24, I haz the power (commit-bot) wrote:
> Try jobs failed on following builders:
>   blink_presubmit on tryserver.blink
>
(http://build.chromium.org/p/tryserver.blink/builders/blink_presubmit/builds/1...)

Oh I thought you're OWNER

[svillar, 2014-08-26 09:12:10]

@jchaffraix, @esprehn: anyone?

[Julien - ping for review, 2014-09-03 20:43:28]

The CQ bit was checked by jchaffraix@chromium.org

[Julien - ping for review, 2014-09-03 20:43:29]

lgtm

[commit-bot: I haz the power, 2014-09-03 20:44:06]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/svillar@igalia.com/488163002/1

[commit-bot: I haz the power, 2014-09-03 20:48:30]

Committed patchset #1 (id:1) as 181339