Remove unneeded loop from LayoutObject::containingBlock.

Remove unneeded loop from LayoutObject::containingBlock.

This code originally was added in
https://chromium.googlesource.com/chromium/blink/+/d27fecb95d6fb60655506f541422fdc532a6c5dc

That megapatch includes it with a comment about positioned element lists
inside LayoutInlines. As best I can tell, that's no longer possible in our
codebase. I can't tell what other useful thing this code could be doing.

Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=197050

[ojan, 2015-06-12 16:23:45]

The CQ bit was checked by ojan@chromium.org to run a CQ dry run

[commit-bot: I haz the power, 2015-06-12 16:23:56]

Dry run: CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1182133002/1

[ojan, 2015-06-12 17:13:59]

ojan@chromium.org changed reviewers:
+ esprehn@chromium.org, mstensho@opera.com

[leviw_travelin_and_unemployed, 2015-06-12 17:29:03]

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

[leviw_travelin_and_unemployed, 2015-06-12 17:29:04]

LGTM.

Maybe file a bug if you intend on continuing to hack on this function/merge it
with container() :)

[commit-bot: I haz the power, 2015-06-12 17:43:10]

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

[commit-bot: I haz the power, 2015-06-12 17:43:11]

Dry run: This issue passed the CQ dry run.

[ojan, 2015-06-12 17:43:48]

The CQ bit was checked by ojan@chromium.org

[commit-bot: I haz the power, 2015-06-12 17:43:57]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1182133002/1

[commit-bot: I haz the power, 2015-06-12 17:46:55]

Committed patchset #1 (id:1) as
https://src.chromium.org/viewvc/blink?view=rev&revision=197050

[mstensho (USE GERRIT), 2015-06-16 08:51:17]

Just a remark here: It was still possible to reach that branch in our codebase.
Consider this:

<span style="position:relative;">
    <div style="position:absolute;"></div>
</span>

We'll end up with a (positioned) LayoutBlock inside a LayoutInline.

As for the usefulness of this... I cannot think of anything (we'll get to the
nearest containing block in due course anyway), so the CL should be good.