Minimal feature collector for select selectors.

Source/core/dom/shadow/SelectRuleFeatureSet.cpp

 /*
  * Copyright (C) 2012 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 14 matching lines @@
  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 #include "config.h"
 #include "core/dom/shadow/SelectRuleFeatureSet.h"
 
 #include "core/css/CSSSelector.h"
+#include "core/css/CSSSelectorList.h"
 
 #include "wtf/BitVector.h"
 
 namespace blink {
 
+void SelectRuleFeatureSet::collectFeaturesFromSelector(const CSSSelector& selector)
+{
+    for (const CSSSelector* current = &selector; current; current = current->tagHistory()) {
+        if (invalidationSetForSelector(*current))
+            continue;
+
+        if (!current->selectorList())
+            continue;
+
+        for (const CSSSelector* selector = current->selectorList()->first(); selector; selector = CSSSelectorList::next(*selector))
+            collectFeaturesFromSelector(*selector);
+    }
+}
+
 bool SelectRuleFeatureSet::checkSelectorsForClassChange(const SpaceSplitString& changedClasses) const
 {
     unsigned changedSize = changedClasses.size();
     for (unsigned i = 0; i < changedSize; ++i) {
         if (hasSelectorForClass(changedClasses[i]))
             return true;
     }
     return false;
 }
 
@@ skipping 30 matching lines @@
 
         // Class was removed.
         if (hasSelectorForClass(oldClasses[i]))
             return true;
     }
     return false;
 }
 
 }