Remove scroll corners and resizers.

Remove scroll corners and resizers.

We never paint scroll corners. The only thing we need them
for is so that the vertical and horizontal scrollbars don't
overlap each other. So, that's the only place left that
still computes a scroll corner rect.

We don't support resizers. Remove the code for them as well
as the CSS resize property.

R=abarth@chromium.org

Committed: https://chromium.googlesource.com/external/mojo/+/46f30fed553e6e8b201d7021382712d3d134c32a

[abarth-chromium, 2014-11-07 15:23:22]

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

[abarth-chromium, 2014-11-07 15:23:24]

lgtm

[abarth-chromium, 2014-11-07 15:23:32]

amazing

[ojan, 2014-11-07 17:46:23]

Committed patchset #1 (id:1) manually as
46f30fed553e6e8b201d7021382712d3d134c32a.