CSSGrid:CSSGrid with responsive props

Build 620 on support-extra-label-on-toggle
1200px
Reviewing disabled
Baseline History
Build 6208266660
Current build. There are unaccepted changes, so build 617 is still the baseline.
Build 6164626d35
Accepted by Steven Hicks.
Build 615cfc7f32
Auto-accepted
Build 614ee5991e
Accepted by Justin Bennett.
Commenting is disabled because there's a newer build on this branch