Use the HashSet of attribute names in SharedStyleFinder.

sky/engine/core/css/resolver/SharedStyleFinder.cpp

Index: sky/engine/core/css/resolver/SharedStyleFinder.cpp
diff --git a/sky/engine/core/css/resolver/SharedStyleFinder.cpp b/sky/engine/core/css/resolver/SharedStyleFinder.cpp
index 5f4ee61d7d4d403c57b3be2c146f403b1f3447cb..d27ad6b233d7196c97a56df0b4cfb99a5b21d65f 100644
--- a/sky/engine/core/css/resolver/SharedStyleFinder.cpp
+++ b/sky/engine/core/css/resolver/SharedStyleFinder.cpp
@@ -48,8 +48,9 @@
 
 namespace blink {
 
-bool SharedStyleFinder::classNamesAffectedByRules(const SpaceSplitString& classNames) const
+bool SharedStyleFinder::classNamesAffectedByRules(const Element& element) const
 {
+    const SpaceSplitString& classNames = element.classNames();
     unsigned count = classNames.size();
     for (unsigned i = 0; i < count; ++i) {
         if (m_features.hasSelectorForClass(classNames[i]))
@@ -58,6 +59,17 @@ bool SharedStyleFinder::classNamesAffectedByRules(const SpaceSplitString& classN
     return false;
 }
 
+bool SharedStyleFinder::attributesAffectedByRules(const Element& element) const
+{
+    AttributeCollection attributes = element.attributesWithoutUpdate();
+    AttributeCollection::iterator end = attributes.end();
+    for (AttributeCollection::iterator it = attributes.begin(); it != end; ++it) {

[ojan, 2014/12/10 23:22:58]

Can you use C++11 iterators here? I think the syntax would be:
for (auto& attribute : element.attributesWithoutUpdate()) {

+        if (m_features.hasSelectorForAttribute(it->localName()))
+            return true;
+    }
+    return false;
+}
+
 bool SharedStyleFinder::sharingCandidateHasIdenticalStyleAffectingAttributes(Element& candidate) const
 {
     if (element().sharesSameElementData(candidate))
@@ -66,7 +78,7 @@ bool SharedStyleFinder::sharingCandidateHasIdenticalStyleAffectingAttributes(Ele
         return false;
 
     if (!m_elementAffectedByClassRules) {
-        if (candidate.hasClass() && classNamesAffectedByRules(candidate.classNames()))
+        if (candidate.hasClass() && classNamesAffectedByRules(candidate))
             return false;
     } else if (candidate.hasClass()) {
         if (element().classNames() != candidate.classNames())
@@ -176,14 +188,6 @@ inline Element* SharedStyleFinder::findElementForStyleSharing() const
     return 0;
 }
 
-bool SharedStyleFinder::matchesRuleSet(RuleSet* ruleSet)
-{
-    if (!ruleSet)
-        return false;
-    ElementRuleCollector collector(m_context);
-    return collector.hasAnyMatchingRules(ruleSet);
-}
-
 RenderStyle* SharedStyleFinder::findSharedStyle()
 {
     INCREMENT_STYLE_STATS_COUNTER(m_styleResolver, sharedStyleLookups);
@@ -191,8 +195,13 @@ RenderStyle* SharedStyleFinder::findSharedStyle()
     if (!element().supportsStyleSharing())
         return 0;
 
+    if (attributesAffectedByRules(element())) {
+        INCREMENT_STYLE_STATS_COUNTER(m_styleResolver, sharedStyleRejectedByAttributeRules);
+        return 0;
+    }
+
     // Cache whether context.element() is affected by any known class selectors.
-    m_elementAffectedByClassRules = element().hasClass() && classNamesAffectedByRules(element().classNames());
+    m_elementAffectedByClassRules = element().hasClass() && classNamesAffectedByRules(element());
 
     Element* shareElement = findElementForStyleSharing();
 
@@ -204,7 +213,7 @@ RenderStyle* SharedStyleFinder::findSharedStyle()
 
     INCREMENT_STYLE_STATS_COUNTER(m_styleResolver, sharedStyleFound);
 
-    if (matchesRuleSet(m_attributeRuleSet)) {
+    if (attributesAffectedByRules(*shareElement)) {
         INCREMENT_STYLE_STATS_COUNTER(m_styleResolver, sharedStyleRejectedByAttributeRules);
         return 0;
     }