Web Animations CSS: Add unsigned short to support outline-width

Web Animations CSS: Add unsigned short to support outline-width

Add unsigned short to animatable factory to support outline-width. The
test animations/interpolation/outline-width.html no longer crashes when
run in the virtual/web-animations-css test suite and no longer overflows
to negative values (correctly clamps to unsigned short) so update test
expectations for that.

Change in behavior here to match Firefox's implementation and align with
the CSS spec (outline-width should not be negative).

BUG=257591
Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=157444

[Steve Block, 2013-09-09 07:38:00]

https://codereview.chromium.org/23548021/diff/1/LayoutTests/virtual/web-anima...
File
LayoutTests/virtual/web-animations-css/animations/interpolation/outline-width-interpolation-expected.txt
(right):

https://codereview.chromium.org/23548021/diff/1/LayoutTests/virtual/web-anima...
LayoutTests/virtual/web-animations-css/animations/interpolation/outline-width-interpolation-expected.txt:2:
PASS: outline-width from [0px] to [10px] was [0px] at -0.3
So now we differ in behavior from the existing implementation, right? Did you
look into whether this will be a safe change when we switch to Web Animations?

[Noel Gordon, 2013-09-09 07:49:41]

On 2013/09/09 07:38:00, Steve Block wrote:

>
https://codereview.chromium.org/23548021/diff/1/LayoutTests/virtual/web-anima...
>
LayoutTests/virtual/web-animations-css/animations/interpolation/outline-width-interpolation-expected.txt:2:
> PASS: outline-width from [0px] to [10px] was [0px] at -0.3
> So now we differ in behavior from the existing implementation, right?
> Did you look into whether this will be a safe change when we switch to Web
Animations?

Indeed there is a change in behavior here to match Firefox's implementation and
align with the spec (outline-width's should not be negative).  Seems safe. 
Added to ChangeLog.

[Steve Block, 2013-09-09 07:51:12]

lgtm

[commit-bot: I haz the power, 2013-09-09 07:56:10]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/noel@chromium.org/23548021/1

[commit-bot: I haz the power, 2013-09-09 07:57:59]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/noel@chromium.org/23548021/1

[commit-bot: I haz the power, 2013-09-09 08:54:25]

Change committed as 157444