[New Multicolumn] Out-of-flow objects don't establish column sets.

[New Multicolumn] Out-of-flow objects don't establish column sets.

If a multicol container only contains out-of-flow objects, there'll be no
column sets, so when determining the need to create one while inserting another
(in-flow) object, we need to ignore out-of-flow objects whose containing block
is not within the flow thread.

BUG=482352
R=dsinclair@chromium.org,jchaffraix@chromium.org

Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=194659

[mstensho (USE GERRIT), 2015-04-29 09:43:11]

I keep finding fuzzer issues. :(

[dsinclair, 2015-04-29 13:31:19]

Fuzzer issues are good, it means we didn't release buggy code. (I get a lot of
fuzzer issues, heh)

lgtm w/ nit.

https://codereview.chromium.org/1110383002/diff/1/Source/core/layout/LayoutMu...
File Source/core/layout/LayoutMultiColumnFlowThread.cpp (right):

https://codereview.chromium.org/1110383002/diff/1/Source/core/layout/LayoutMu...
Source/core/layout/LayoutMultiColumnFlowThread.cpp:536: // First skip objects
that do not have this flow thread in their containing block
This comment is a bit confusing given it's placement. I'd expect the next if()
to be skipping things, but, in fact it's dealing with in-flow objects which did
create a column set. It might be better as something like:


Walk through the children and find the first child which is either in-flow or
has this flow thread as its containing block flow thread.

(Assuming I'm reading the below correctly?)

[mstensho (USE GERRIT), 2015-04-29 13:52:21]

https://codereview.chromium.org/1110383002/diff/1/Source/core/layout/LayoutMu...
File Source/core/layout/LayoutMultiColumnFlowThread.cpp (right):

https://codereview.chromium.org/1110383002/diff/1/Source/core/layout/LayoutMu...
Source/core/layout/LayoutMultiColumnFlowThread.cpp:536: // First skip objects
that do not have this flow thread in their containing block
On 2015/04/29 13:31:19, dsinclair wrote:
> This comment is a bit confusing given it's placement. I'd expect the next if()
> to be skipping things, but, in fact it's dealing with in-flow objects which
did
> create a column set. It might be better as something like:
> 
> 
> Walk through the children and find the first child which is either in-flow or
> has this flow thread as its containing block flow thread.
> 
> (Assuming I'm reading the below correctly?)

That works, except that it's siblings (or aunts), not children. :)

Done.

[mstensho (USE GERRIT), 2015-04-29 13:52:30]

The CQ bit was checked by mstensho@opera.com

[mstensho (USE GERRIT), 2015-04-29 13:52:30]

The patchset sent to the CQ was uploaded after l-g-t-m from
dsinclair@chromium.org
Link to the patchset: https://codereview.chromium.org/1110383002/#ps20001
(title: "code review.")

[commit-bot: I haz the power, 2015-04-29 13:52:35]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1110383002/20001

[commit-bot: I haz the power, 2015-04-29 15:04:14]

Committed patchset #2 (id:20001) as
https://src.chromium.org/viewvc/blink?view=rev&revision=194659