Implement ::content

Source/core/css/CSSSelector.cpp

Index: Source/core/css/CSSSelector.cpp
diff --git a/Source/core/css/CSSSelector.cpp b/Source/core/css/CSSSelector.cpp
index c32ec173cd4d4c935ed17105c67027340fded3d0..c3ac0221afb394407d4c4ea972eb28e2f07af932 100644
--- a/Source/core/css/CSSSelector.cpp
+++ b/Source/core/css/CSSSelector.cpp
@@ -337,6 +337,7 @@ static HashMap<StringImpl*, CSSSelector::PseudoType>* nameToPseudoTypeMap()
     DEFINE_STATIC_LOCAL(AtomicString, outOfRange, ("out-of-range", AtomicString::ConstructFromLiteral));
     DEFINE_STATIC_LOCAL(AtomicString, scope, ("scope", AtomicString::ConstructFromLiteral));
     DEFINE_STATIC_LOCAL(AtomicString, unresolved, ("unresolved", AtomicString::ConstructFromLiteral));
+    DEFINE_STATIC_LOCAL(AtomicString, content, ("content", AtomicString::ConstructFromLiteral));
 
     static HashMap<StringImpl*, CSSSelector::PseudoType>* nameToPseudoType = 0;
     if (!nameToPseudoType) {
@@ -418,6 +419,8 @@ static HashMap<StringImpl*, CSSSelector::PseudoType>* nameToPseudoTypeMap()
         nameToPseudoType->set(outOfRange.impl(), CSSSelector::PseudoOutOfRange);
         if (RuntimeEnabledFeatures::customDOMElementsEnabled())
             nameToPseudoType->set(unresolved.impl(), CSSSelector::PseudoUnresolved);
+        if (RuntimeEnabledFeatures::shadowDOMEnabled())
+            nameToPseudoType->set(content.impl(), CSSSelector::PseudoContent);
     }
     return nameToPseudoType;
 }
@@ -470,6 +473,7 @@ void CSSSelector::extractPseudoType() const
     case PseudoSelection:
     case PseudoUserAgentCustomElement:
     case PseudoWebKitCustomElement:
+    case PseudoContent:
         element = true;
         break;
     case PseudoUnknown:
@@ -637,6 +641,8 @@ String CSSSelector::selectorText(const String& rightSide) const
         } else if (cs->m_match == CSSSelector::PseudoElement) {
             str.appendLiteral("::");
             str.append(cs->value());
+            if (cs->pseudoType() == CSSSelector::PseudoContent && cs->relation() == CSSSelector::SubSelector && cs->tagHistory())
+                return cs->tagHistory()->selectorText() + str.toString() + rightSide;
         } else if (cs->isAttributeSelector()) {
             str.append('[');
             const AtomicString& prefix = cs->attribute().prefix();
@@ -684,11 +690,11 @@ String CSSSelector::selectorText(const String& rightSide) const
     if (const CSSSelector* tagHistory = cs->tagHistory()) {
         switch (cs->relation()) {
         case CSSSelector::Descendant:
-            if (cs->relationIsForShadowDistributed())
+            if (cs->relationIsForShadowDistributed() && tagHistory->pseudoType() != CSSSelector::PseudoContent)
                 return tagHistory->selectorText("::-webkit-distributed(" + str.toString() + rightSide + ")");
             return tagHistory->selectorText(" " + str.toString() + rightSide);
         case CSSSelector::Child:
-            if (cs->relationIsForShadowDistributed())
+            if (cs->relationIsForShadowDistributed() && tagHistory->pseudoType() != CSSSelector::PseudoContent)
                 return tagHistory->selectorText("::-webkit-distributed(> " + str.toString() + rightSide + ")");
             return tagHistory->selectorText(" > " + str.toString() + rightSide);
         case CSSSelector::DirectAdjacent: