Handle closed mode shadow for /deep/ and ::shadow selectors

Source/core/css/SelectorChecker.cpp

Index: Source/core/css/SelectorChecker.cpp
diff --git a/Source/core/css/SelectorChecker.cpp b/Source/core/css/SelectorChecker.cpp
index 45134f9de9d78959dbf1e6d710c414dcf91105de..2d0337e5ea8c69fe85827812b2f1e0a6016217ce 100644
--- a/Source/core/css/SelectorChecker.cpp
+++ b/Source/core/css/SelectorChecker.cpp
@@ -309,6 +309,15 @@ SelectorChecker::Match SelectorChecker::matchForPseudoShadow(const SelectorCheck
     return matchSelector(context, result);
 }
 
+static inline Element* parentOrOpenShadowHostElement(const Element* element)

[hayato, 2015/08/20 07:09:59]

This might be confusing name because shadow host's open-ness is irrelevant here.
Could it have better name?

[hayato, 2015/08/20 07:09:59]

const Element&

[kochi, 2015/08/20 07:32:50]

How about parentOrShadowHostElementWithoutExceedingClosedBoundary()?

[kochi, 2015/08/20 07:32:50]

Done.

[hayato, 2015/08/20 10:16:29]

I would prefer parentOrShadowHostButDisallowEscapingClosedShadowTree, which was
the former name. :)

I'd like to avoid using a term of *boundary* in general becase the spec doesn'
define it.

+{
+    if (element->parentNode() && element->parentNode()->isShadowRoot()) {
+        if (!toShadowRoot(element->parentNode())->isOpen())
+            return nullptr;
+    }
+    return element->parentOrShadowHostElement();
+}
+
 SelectorChecker::Match SelectorChecker::matchForRelation(const SelectorCheckingContext& context, MatchResult& result) const
 {
     SelectorCheckingContext nextContext = prepareNextContextForRelation(context);
@@ -423,6 +432,7 @@ SelectorChecker::Match SelectorChecker::matchForRelation(const SelectorCheckingC
             }
 
             if (context.selector->relationIsAffectedByPseudoContent()) {
+                // TODO(kochi): closed mode tree should be handled as well for ::content.

[kochi, 2015/08/20 06:04:26]

Added TODO for fixing this later.

                 for (Element* element = context.element; element; element = element->parentOrShadowHostElement()) {
                     if (matchForShadowDistributed(nextContext, *element, result) == SelectorMatches)
                         return SelectorMatches;
@@ -432,7 +442,8 @@ SelectorChecker::Match SelectorChecker::matchForRelation(const SelectorCheckingC
 
             nextContext.isSubSelector = false;
             nextContext.inRightmostCompound = false;
-            for (nextContext.element = context.element->parentOrShadowHostElement(); nextContext.element; nextContext.element = nextContext.element->parentOrShadowHostElement()) {
+
+            for (nextContext.element = parentOrOpenShadowHostElement(context.element); nextContext.element; nextContext.element = parentOrOpenShadowHostElement(nextContext.element)) {
                 Match match = matchSelector(nextContext, result);
                 if (match == SelectorMatches || match == SelectorFailsCompletely)
                     return match;