Enable slimming paint for css1/, css2.1/ and css3/

Enable slimming paint for css1/, css2.1/ and css3/

All NeedsRebaselines are because of
- border anti-aliasing changes;
- text-based-repaint result format changes.

BUG=497950
TBR=chrishtr@chromium.org,wkorman@chromium.org

Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=197405

[Xianzhu, 2015-06-18 16:59:19]

wangxianzhu@chromium.org changed reviewers:
+ chrishtr@chromium.org, wkorman@chromium.org

[Xianzhu, 2015-06-18 17:00:16]

The CQ bit was checked by wangxianzhu@chromium.org

[commit-bot: I haz the power, 2015-06-18 17:00:40]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1188313002/80001

[Xianzhu, 2015-06-18 18:09:31]

The CQ bit was unchecked by wangxianzhu@chromium.org

[Xianzhu, 2015-06-18 19:14:59]

The CQ bit was checked by wangxianzhu@chromium.org

[commit-bot: I haz the power, 2015-06-18 19:15:54]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1188313002/80001

[Xianzhu, 2015-06-18 21:20:27]

The CQ bit was unchecked by wangxianzhu@chromium.org

[Xianzhu, 2015-06-18 22:42:59]

The CQ bit was checked by wangxianzhu@chromium.org

[commit-bot: I haz the power, 2015-06-18 22:43:17]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1188313002/80001

[commit-bot: I haz the power, 2015-06-18 22:47:57]

Committed patchset #5 (id:80001) as
https://src.chromium.org/viewvc/blink?view=rev&revision=197405