Allow whitespace at end of :not() pseudo-class, i.e. :not(div )

Allow whitespace at end of :not() pseudo-class, i.e. :not(div )

This patch fixes a bug in the (new) CSS selector parser where we would
reject :not() pseudo-classes with trailing whitespace. Note that our
current implementation or :not() is partway between the level 3 and 4
specs, where we allow compound selectors instead of simple selectors
and selector lists respectively.

BUG=482221
Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=194795

[Timothy Loh, 2015-05-01 04:41:23]

timloh@chromium.org changed reviewers:
+ alancutter@chromium.org, dstockwell@chromium.org

[dstockwell, 2015-05-01 06:37:01]

The CQ bit was checked by dstockwell@chromium.org

[dstockwell, 2015-05-01 06:37:02]

lgtm

[commit-bot: I haz the power, 2015-05-01 06:37:15]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1119983002/1

[commit-bot: I haz the power, 2015-05-01 07:46:47]

Committed patchset #1 (id:1) as
https://src.chromium.org/viewvc/blink?view=rev&revision=194795