Properly avoid breaking inside a float's top margin.

Properly avoid breaking inside a float's top margin.

We used to depend on stumbling upon unbreakable content (such as lines) at
column boundaries for this to work, but we failed in the really simple cases
(where there was no content at all, for instance).

Move the logic for this to float-specific code, so that we don't have to be
aware of it at several other locations in the code.

Doing this correctly during layout also helps the balancer find the right
column height. Added a test for something that used to fail in this area.

Committed: https://crrev.com/c8e6a3cc38e6ca93572e9390d1910b81816e089a
Cr-Commit-Position: refs/heads/master@{#429641}

[mstensho (USE GERRIT), 2016-11-03 08:27:37]

The CQ bit was checked by mstensho@opera.com to run a CQ dry run

[commit-bot: I haz the power, 2016-11-03 08:27:52]

Dry run: CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[mstensho (USE GERRIT), 2016-11-03 10:15:01]

mstensho@opera.com changed reviewers:
+ eae@chromium.org

[commit-bot: I haz the power, 2016-11-03 10:28:20]

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

[commit-bot: I haz the power, 2016-11-03 10:28:21]

Dry run: Try jobs failed on following builders:
  linux_chromium_asan_rel_ng on master.tryserver.chromium.linux (JOB_TIMED_OUT,
no build URL)

[eae, 2016-11-03 16:15:54]

Nice! LGTM

[mstensho (USE GERRIT), 2016-11-03 16:27:20]

The CQ bit was checked by mstensho@opera.com

[commit-bot: I haz the power, 2016-11-03 16:27:54]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2016-11-03 17:50:59]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2016-11-03 18:14:22]

Description was changed from

==========
Properly avoid breaking inside a float's top margin.

We used to depend on stumbling upon unbreakable content (such as lines) at
column boundaries for this to work, but we failed in the really simple cases
(where there was no content at all, for instance).

Move the logic for this to float-specific code, so that we don't have to be
aware of it at several other locations in the code.

Doing this correctly during layout also helps the balancer find the right
column height. Added a test for something that used to fail in this area.
==========

to

==========
Properly avoid breaking inside a float's top margin.

We used to depend on stumbling upon unbreakable content (such as lines) at
column boundaries for this to work, but we failed in the really simple cases
(where there was no content at all, for instance).

Move the logic for this to float-specific code, so that we don't have to be
aware of it at several other locations in the code.

Doing this correctly during layout also helps the balancer find the right
column height. Added a test for something that used to fail in this area.

Committed: https://crrev.com/c8e6a3cc38e6ca93572e9390d1910b81816e089a
Cr-Commit-Position: refs/heads/master@{#429641}
==========

[commit-bot: I haz the power, 2016-11-03 18:14:23]

Patchset 1 (id:??) landed as
https://crrev.com/c8e6a3cc38e6ca93572e9390d1910b81816e089a
Cr-Commit-Position: refs/heads/master@{#429641}