Clear matched properties cache for theme color changes.

Clear matched properties cache for theme color changes.

A theme dependent color is represented by a keyword in CSS and the matched
property value won't change when the theme color changes. That lead to a
cache hit in MatchPropertiesCache so that a style recalc after changing the
theme wouldn't have an effect. So, we need to invalidate the cache on such
changes.

Changed method name and api layering to contain knowledge about necessary
changes in the StyleEngine.

BUG=441144
Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=187517

[rune, 2014-12-18 10:59:39]

rune@opera.com changed reviewers:
+ timloh@chromium.org

[Timothy Loh, 2014-12-18 22:52:55]

On 2014/12/18 10:59:40, rune wrote:

lgtm

[rune, 2014-12-18 22:56:33]

The CQ bit was checked by rune@opera.com

[commit-bot: I haz the power, 2014-12-18 22:57:18]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/804873003/1

[commit-bot: I haz the power, 2014-12-19 02:07:47]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2014-12-19 02:07:48]

Internal error: failed to checkout. Please try again.

[rune, 2014-12-19 07:01:52]

The CQ bit was checked by rune@opera.com

[commit-bot: I haz the power, 2014-12-19 07:02:10]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/804873003/1

[commit-bot: I haz the power, 2014-12-19 08:37:12]

Committed patchset #1 (id:1) as
https://src.chromium.org/viewvc/blink?view=rev&revision=187517