Removed O(n!) traversal of selectors for selectorList.

Removed O(n!) traversal of selectors for selectorList.

When collectFeaturesFromSelector got a for-loop for tagHistory in [1], the
for-loop for tagHistory was kept in collectFeaturesFromSelectorList which
means we did n! visits of n sub-selectors in selectors like
:-webkit-any(.a.b.c).

[1] https://codereview.chromium.org/143653010

R=esprehn,chrishtr
BUG=335247
Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=167475

[esprehn, 2014-02-19 21:41:44]

Woah, lgtm. n! eh?

[esprehn, 2014-02-19 21:41:47]

The CQ bit was checked by esprehn@chromium.org

[rune, 2014-02-19 21:46:58]

On 2014/02/19 21:41:44, esprehn wrote:
> Woah, lgtm. n! eh?

n tends to be very close to 1 in these cases, though. :-)

[commit-bot: I haz the power, 2014-02-19 22:05:30]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/rune@opera.com/172993002/1

[chrishtr, 2014-02-19 22:44:08]

lgtm

[commit-bot: I haz the power, 2014-02-19 23:10:41]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/rune@opera.com/172993002/1

[commit-bot: I haz the power, 2014-02-20 07:40:58]

Change committed as 167475