Remove unused functions from ElementRuleCollector

This patch removes the functions:
- lastMatchedRulesPosition
- sortMatchedRulesFrom
- sortAndTransferMatchedRulesWithOnlySortBySpecificity
from ElementRuleCollector as they are unused (and the latter two don't
even have definitions).

Review URL: https://codereview.chromium.org/460263002

git-svn-id: svn://svn.chromium.org/blink/trunk@180054 bbb929c8-8fbe-4397-9dbb-9b2b20218538

third_party/WebKit/Source/core/css/ElementRuleCollector.h

@@ -131,10 +131,6 @@ public:
     void clearMatchedRules();
     void addElementStyleProperties(const StylePropertySet*, bool isCacheable = true);
 
-    unsigned lastMatchedRulesPosition() const { return m_matchedRules ? m_matchedRules->size() : 0; }
-    void sortMatchedRulesFrom(unsigned position);
-    void sortAndTransferMatchedRulesWithOnlySortBySpecificity();
-
 private:
     void collectRuleIfMatches(const RuleData&, SelectorChecker::ContextFlags, CascadeScope, CascadeOrder, const MatchRequest&, RuleRange&);