Added UNLIKELY() suggested in https://bugs.webkit.org/show_bug.cgi?id=114366
after checking in the original change.

Rubber-stamped by Jessie Berlin.

* dfg/DFGOperations.cpp:


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@148207 268f45cc-cd09-0410-ab3c-d52691b4dbfc
Use CSS4 image-rendering to determing image scaling quality
https://bugs.webkit.org/show_bug.cgi?id=113405

Reviewed by Simon Fraser.

Source/WebCore:

Implement the new CSS4 image-rendering property values.

Image scaling now uses low-quality (pixelated) scaling for
crisp-edges, pixelated and optimizeSpeed values, and always
use high quality (smooth) scaling for -webkit-smooth and
optimizeQuality. The latter can be used to disable low quality
scaling during CSS animations or live resizing.

The new values are protected with a new CSS4_IMAGES feature, but
the crisp-edge value has been introduced before to displace the
deprecated -webkit-optimize-contrast value, and optimizeSpeed
and optimizeQuality values are supported for SVG compatibility.

* css/CSSParser.cpp:
(WebCore::isValidKeywordPropertyAndValue):
* css/CSSPrimitiveValueMappings.h:
(WebCore::CSSPrimitiveValue::CSSPrimitiveValue):
(WebCore::CSSPrimitiveValue::operator EImageRendering):
* css/CSSValueKeywords.in:
* rendering/RenderBoxModelObject.cpp:
(WebCore::ImageQualityController::shouldPaintAtLowQuality):
* rendering/RenderHTMLCanvas.cpp:
(WebCore::RenderHTMLCanvas::paintReplaced):
* rendering/style/RenderStyleConstants.h:

Tools:

Introduce new flag to enable experimental support for CSS4 Images.

* Scripts/webkitperl/FeatureList.pm:

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@148208 268f45cc-cd09-0410-ab3c-d52691b4dbfc