REGRESSION (r95502): Assertion failure in CSSPrimitiveValue::computeLengthDouble...

REGRESSION (r95502): Assertion failure in CSSPrimitiveValue::computeLengthDouble() when media query specifies unit-less length
https://bugs.webkit.org/show_bug.cgi?id=68760

Reviewed by Antti Koivisto.

Source/WebCore:

Test: fast/media/invalid-lengths.html

Made length-comparison media queries accept only length values. In compatibility mode, numbers
are allowed as well, and they are interpreted as pixels.

* css/MediaQueryEvaluator.cpp:
(WebCore::computeLength): Added this helper function.
(WebCore::device_heightMediaFeatureEval): Changed to use computeLength().
(WebCore::device_widthMediaFeatureEval): Ditto.
(WebCore::heightMediaFeatureEval): Ditto.
(WebCore::widthMediaFeatureEval): Ditto.

LayoutTests:

* fast/media/invalid-lengths-expected.txt: Added.
* fast/media/invalid-lengths.html: Added.

git-svn-id: https://svn.webkit.org/repository/webkit/trunk@96471 268f45cc-cd09-0410-ab3c-d52691b4dbfc