Don't transition a property that is currentColor when color changes

Don't transition a property that is currentColor when color changes

As per css3-color[1], currentColor is not resolved at computed value
time. This means that we shouldn't fire a transition when a property is
set to currentColor, even if the used value changes. Note we still
transition between currentColor and actual colours, which is likely to
be fine by css4-color, which adds a blending primitive.

[1] http://www.w3.org/Style/2011/REC-css3-color-20110607-errata.html

BUG=394632
Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=181546

[Timothy Loh, 2014-09-08 06:23:10]

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

[Timothy Loh, 2014-09-08 06:25:35]

I suspect this is slightly inconsistent with other uses of color (shadows,
filters, gradients), but those currently resolve currentColor during style
resolution so we can't easily make those behave the same here.

[alancutter (OOO until 2018), 2014-09-08 06:41:41]

lgtm assuming there's a test somewhere that checks the values used to transition
between currentcolor and concrete colours are correct.

[Timothy Loh, 2014-09-08 07:04:39]

On 2014/09/08 06:41:41, alancutter wrote:
> lgtm assuming there's a test somewhere that checks the values used to
transition
> between currentcolor and concrete colours are correct.

I extended the added test slightly to check that we'll transition in this case.

[Timothy Loh, 2014-09-08 07:04:43]

The CQ bit was checked by timloh@chromium.org

[commit-bot: I haz the power, 2014-09-08 07:05:41]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/timloh@chromium.org/552683002/20001

[commit-bot: I haz the power, 2014-09-08 07:25:49]

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

[commit-bot: I haz the power, 2014-09-08 07:25:50]

Try jobs failed on following builders:
  win_gpu on tryserver.chromium.gpu
(http://build.chromium.org/p/tryserver.chromium.gpu/builders/win_gpu/builds/57739)

[Timothy Loh, 2014-09-08 08:18:13]

The CQ bit was checked by timloh@chromium.org

[commit-bot: I haz the power, 2014-09-08 08:19:09]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/timloh@chromium.org/552683002/20001

[commit-bot: I haz the power, 2014-09-08 08:58:35]

Committed patchset #2 (id:20001) as 181546