Self-collapsing blocks shouldn't get layout bit sit when handling margins

Self-collapsing blocks shouldn't get layout bit sit when handling margins

marginOffsetForSelfCollapsingBlock() was interested in any clearance a self-collapsing
block has due to 'clear:' in its style. Once a block has been laid out it can't
actually tell this anymore! So instead, watch for clearance happening and store
it in marginInfo so that we can use it to update the block position for margin
collapsing.

BUG=479562
Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=197185

[rhogan, 2015-06-16 17:19:34]

robhogan@gmail.com changed reviewers:
+ ojan@chromium.org

[ojan, 2015-06-16 17:41:57]

ojan@chromium.org changed reviewers:
+ leviw@chromium.org

[ojan, 2015-06-16 17:41:57]

Levi, do you think you'll have time to review this?

[leviw_travelin_and_unemployed, 2015-06-16 17:52:59]

CSS makes this so complicated.

I'm glad I have this margin crap relatively paged in right now.

LGTM.

https://codereview.chromium.org/1157863014/diff/60001/Source/core/layout/Layo...
File Source/core/layout/LayoutBlockFlow.cpp (right):

https://codereview.chromium.org/1157863014/diff/60001/Source/core/layout/Layo...
Source/core/layout/LayoutBlockFlow.cpp:1837: LayoutRect borderBox =
child->borderBoxRect();
This was just uselessly inside the loop before? *sigh*.

[rhogan, 2015-06-16 18:17:09]

The CQ bit was checked by robhogan@gmail.com

[commit-bot: I haz the power, 2015-06-16 18:17:53]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1157863014/60001

[commit-bot: I haz the power, 2015-06-16 19:08:06]

Committed patchset #4 (id:60001) as
https://src.chromium.org/viewvc/blink?view=rev&revision=197185