Use the HashSet of attribute names in SharedStyleFinder.

sky/engine/core/css/ElementRuleCollector.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 2004-2005 Allan Sandfeld Jensen (kde@carewolf.com)
  * Copyright (C) 2006, 2007 Nicholas Shanks (webkit@nickshanks.com)
  * Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013 Apple Inc. All rights reserved.
  * Copyright (C) 2007 Alexey Proskuryakov <ap@webkit.org>
  * Copyright (C) 2007, 2008 Eric Seidel <eric@webkit.org>
  * Copyright (C) 2008, 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
  * Copyright (c) 2011, Code Aurora Forum. All rights reserved.
  * Copyright (C) Research In Motion Limited 2011. All rights reserved.
@@ skipping 173 matching lines @@
 
     return matchedRule1.position() < matchedRule2.position();
 }
 
 void ElementRuleCollector::sortMatchedRules()
 {
     ASSERT(m_matchedRules);
     std::sort(m_matchedRules->begin(), m_matchedRules->end(), compareRules);
 }
 
-bool ElementRuleCollector::hasAnyMatchingRules(RuleSet* ruleSet)
-{
-    clearMatchedRules();
-
-    m_mode = SelectorChecker::SharingRules;
-    // To check whether a given RuleSet has any rule matching a given element,
-    // should not see the element's treescope. Because RuleSet has no
-    // information about "scope".
-    int firstRuleIndex = -1, lastRuleIndex = -1;
-    RuleRange ruleRange(firstRuleIndex, lastRuleIndex);
-    // FIXME: Verify whether it's ok to ignore CascadeScope here.
-    collectMatchingRules(MatchRequest(ruleSet), ruleRange, SelectorChecker::DefaultBehavior);
-
-    return m_matchedRules && !m_matchedRules->isEmpty();
-}
-
 } // namespace blink