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
Review URL: https://codereview.chromium.org/689283003
The two are unrelated, but it was easier to just grep for grid
and remove them all. Aside from the media query change, there
isn't any change in behavior since grid was behind a flag.
R=esprehn@chromium.org
Review URL: https://codereview.chromium.org/689853003
