Use CSSParserSelector::appendTagHistory() from CSS grammar.
<http://webkit.org/b/116382>

Reviewed by Antti Koivisto.

CSSParserSelector already knows how to append another component to itself,
no need to duplicate that logic in the grammar.

* css/CSSGrammar.y.in:


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@150337 268f45cc-cd09-0410-ab3c-d52691b4dbfc