Remove dead StyleRuleFilter.

sky/engine/core/css/StyleRule.cpp

 /*
  * (C) 1999-2003 Lars Knoll (knoll@kde.org)
  * (C) 2002-2003 Dirk Mueller (mueller@kde.org)
  * Copyright (C) 2002, 2005, 2006, 2008, 2012 Apple Inc. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
@@ skipping 33 matching lines @@
         return;
     case Media:
         delete toStyleRuleMedia(this);
         return;
     case Supports:
         delete toStyleRuleSupports(this);
         return;
     case Keyframes:
         delete toStyleRuleKeyframes(this);
         return;
-    case Filter:
-        delete toStyleRuleFilter(this);
-        return;
     case Unknown:
     case Keyframe:
         ASSERT_NOT_REACHED();
         return;
     }
     ASSERT_NOT_REACHED();
 }
 
 unsigned StyleRule::averageSizeInBytes()
 {
@@ skipping 40 matching lines @@
 {
 }
 
 StyleRuleSupports::StyleRuleSupports(const String& conditionText, bool conditionIsSupported, Vector<RefPtr<StyleRuleBase> >& adoptRules)
     : StyleRuleGroup(Supports, adoptRules)
     , m_conditionText(conditionText)
     , m_conditionIsSupported(conditionIsSupported)
 {
 }
 
-StyleRuleFilter::StyleRuleFilter(const String& filterName)
-    : StyleRuleBase(Filter)
-    , m_filterName(filterName)
-{
-}
-
-StyleRuleFilter::~StyleRuleFilter()
-{
-}
-
-void StyleRuleFilter::setProperties(PassRefPtr<StylePropertySet> properties)
-{
-    m_properties = properties;
-}
-
 } // namespace blink