Remove contextStyleSheet argument from CSSValuePool::createFontFaceValue().

Remove contextStyleSheet argument from CSSValuePool::createFontFaceValue().
<http://webkit.org/b/83988>

Reviewed by Antti Koivisto.

Remove the 'context style sheet' argument to <font face> value parsing.
It was only ever used to grab at the CSSValuePool back when they were per-Document.

* css/CSSParser.h:
* css/CSSParser.cpp:
(WebCore::CSSParser::parseFontFaceValue):
* css/CSSValuePool.h:
* css/CSSValuePool.cpp:
(WebCore::CSSValuePool::createFontFaceValue):
* html/HTMLFontElement.cpp:
(WebCore::HTMLFontElement::collectStyleForAttribute):

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@114325 268f45cc-cd09-0410-ab3c-d52691b4dbfc