Implement runtime feature support for CSS Shorthands

Implement runtime feature support for CSS Shorthands

Some newly implemented shorthand properties (eg. text-decoration) are 
only allowed if a runtime feature is enabled, with fallback to regular
non-shorthand parsing otherwise. This patch adds a 
'runtimeEnabledShorthand' optional variable that must contain the name
of the runtime feature (eg. CSS3TextDecorations).

This fixes an issue where an assertion in StyleResolver indicated that
it expected a shorthand property (see link below for details):
https://codereview.chromium.org/20262002/#msg28

BUG=165462
Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=155866

[abinader, 2013-08-08 21:27:48]

This adds support for runtime feature check in CSSShorthands.in.

[darktears, 2013-08-09 16:43:14]

On 2013/08/08 21:27:48, abinader wrote:
> This adds support for runtime feature check in CSSShorthands.in.

LGTM.

[Julien - ping for review, 2013-08-09 16:47:30]

lgtm.

> Some newly implemented shorthand properties (eg. text-decoration) are enabled
in runtime.

This is not a totally accurate description: your issue is that a flag determines
whether we parse the property by itself or as a shorthand.

New shorthands are usually new properties and thus wouldn't need this flag as
they are rejected at parse-time based on the flag.

https://codereview.chromium.org/22610005/diff/5001/Source/core/scripts/make_s...
File Source/core/scripts/make_style_shorthands.py (right):

https://codereview.chromium.org/22610005/diff/5001/Source/core/scripts/make_s...
Source/core/scripts/make_style_shorthands.py:43: 'runtimeConditional': None,
I would rename this to is 'runtimeEnabledShorthand' to emphasize the point
above.

https://codereview.chromium.org/22610005/diff/5001/Source/core/scripts/make_s...
Source/core/scripts/make_style_shorthands.py:82: lowered =
lowered.replace("wOFF", "woff")
This seems like an overkill to list all these as we don't expect them to switch
anytime soon. I would just keep the CSS mapping as you will use it.

[abinader, 2013-08-09 16:52:21]

On 2013/08/09 16:47:30, Julien Chaffraix wrote:
> lgtm.
> 
> > Some newly implemented shorthand properties (eg. text-decoration) are
enabled
> in runtime.
> 
> This is not a totally accurate description: your issue is that a flag
determines
> whether we parse the property by itself or as a shorthand.
> 
> New shorthands are usually new properties and thus wouldn't need this flag as
> they are rejected at parse-time based on the flag.

Ok, I'll update the patch comments to better reflect that.

>
https://codereview.chromium.org/22610005/diff/5001/Source/core/scripts/make_s...
> File Source/core/scripts/make_style_shorthands.py (right):
> 
>
https://codereview.chromium.org/22610005/diff/5001/Source/core/scripts/make_s...
> Source/core/scripts/make_style_shorthands.py:43: 'runtimeConditional': None,
> I would rename this to is 'runtimeEnabledShorthand' to emphasize the point
> above.

Ack.

>
https://codereview.chromium.org/22610005/diff/5001/Source/core/scripts/make_s...
> Source/core/scripts/make_style_shorthands.py:82: lowered =
> lowered.replace("wOFF", "woff")
> This seems like an overkill to list all these as we don't expect them to
switch
> anytime soon. I would just keep the CSS mapping as you will use it.

Ack. That's actually one of the reasons we should move these helper functions to
a utils section, which would be shared among all scripts (to avoid code
duplication), as Alexis mentioned on his FIXME note.

[commit-bot: I haz the power, 2013-08-09 18:06:31]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/bruno.d@partner.samsung.com/22610005/1...

[commit-bot: I haz the power, 2013-08-09 20:40:24]

Change committed as 155866