No pseudo elements in SelectorChecker::Mode QueryingRules.

third_party/WebKit/Source/core/dom/SelectorQuery.cpp

Index: third_party/WebKit/Source/core/dom/SelectorQuery.cpp
diff --git a/third_party/WebKit/Source/core/dom/SelectorQuery.cpp b/third_party/WebKit/Source/core/dom/SelectorQuery.cpp
index 37dbb07d7b9f13cb226c907fc9ebaf572d6cd496..5f564799ea05ecb9bf5fcb9b88a5f8f9dbb879b8 100644
--- a/third_party/WebKit/Source/core/dom/SelectorQuery.cpp
+++ b/third_party/WebKit/Source/core/dom/SelectorQuery.cpp
@@ -109,10 +109,13 @@ void SelectorDataList::initialize(const CSSSelectorList& selectorList)
     m_needsUpdatedDistribution = false;
     m_selectors.reserveInitialCapacity(selectorCount);
     unsigned index = 0;
-    for (const CSSSelector* selector = selectorList.first(); selector; selector = CSSSelectorList::next(*selector), ++index) {
+    for (const CSSSelector* selector = selectorList.first(); selector; selector = CSSSelectorList::next(*selector)) {
+        if (selector->matchesPseudoElement())
+            continue;

[esprehn, 2016/01/29 02:42:17]

why is it safe not to increment index here? That means we're going to move to
the next selector above, but still look at the previous selector below.

[rune, 2016/01/29 09:53:20]

Ouch, that's not correct. Will fix.

[rune, 2016/01/29 10:58:43]

Done.

         m_selectors.uncheckedAppend(selector);
         m_usesDeepCombinatorOrShadowPseudo |= selectorList.selectorUsesDeepCombinatorOrShadowPseudo(index);
         m_needsUpdatedDistribution |= selectorList.selectorNeedsUpdatedDistribution(index);
+        ++index;
     }
 }
 
@@ -141,10 +144,13 @@ bool SelectorDataList::matches(Element& targetElement) const
 
 Element* SelectorDataList::closest(Element& targetElement) const
 {
+    unsigned selectorCount = m_selectors.size();
+    if (!selectorCount)
+        return nullptr;
+
     if (m_needsUpdatedDistribution)
         targetElement.updateDistribution();
 
-    unsigned selectorCount = m_selectors.size();
     for (Element* currentElement = &targetElement; currentElement; currentElement = currentElement->parentElement()) {
         for (unsigned i = 0; i < selectorCount; ++i) {
             if (selectorMatches(*m_selectors[i], *currentElement, targetElement))
@@ -451,6 +457,9 @@ const CSSSelector* SelectorDataList::selectorForIdLookup(const CSSSelector& firs
 template <typename SelectorQueryTrait>
 void SelectorDataList::execute(ContainerNode& rootNode, typename SelectorQueryTrait::OutputType& output) const
 {
+    if (!m_selectors.size())
+        return;
+
     if (!canUseFastQuery(rootNode)) {
         if (m_needsUpdatedDistribution)
             rootNode.updateDistribution();