Remove unneeded 1px vertical offset for left/right double box sides

Remove unneeded 1px vertical offset for left/right double box sides

Not only unneeded, but also causing corner artifacts in some cases.

R=chrishtr@chromium.org,junov@chromium.org
BUG=473119
Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=196261

[f(malita), 2015-06-01 20:07:44]

fmalita@chromium.org changed reviewers:
+ junov@chromium.org

[f(malita), 2015-06-01 20:10:09]

A handful of trivial/expected layout test diffs:
https://storage.googleapis.com/chromium-layout-test-archives/linux_blink_rel/...

[chrishtr, 2015-06-01 20:19:08]

The CQ bit was checked by chrishtr@chromium.org

[chrishtr, 2015-06-01 20:19:09]

lgtm

[commit-bot: I haz the power, 2015-06-01 20:20:39]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1146313005/40001

[f(malita), 2015-06-01 22:13:34]

The CQ bit was unchecked by fmalita@chromium.org

[f(malita), 2015-06-01 22:13:42]

The CQ bit was checked by fmalita@chromium.org

[commit-bot: I haz the power, 2015-06-01 23:34:12]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1146313005/40001

[commit-bot: I haz the power, 2015-06-02 00:37:07]

Committed patchset #3 (id:40001) as
https://src.chromium.org/viewvc/blink?view=rev&revision=196261