Implement :defined pseudo-class selector for Custom Elements

third_party/WebKit/Source/core/css/RuleFeature.cpp

Index: third_party/WebKit/Source/core/css/RuleFeature.cpp
diff --git a/third_party/WebKit/Source/core/css/RuleFeature.cpp b/third_party/WebKit/Source/core/css/RuleFeature.cpp
index 24500d66cc7ce93208d3595f68f67d3d25ecb76a..6284b30302380f93d0f84389385077434595150f 100644
--- a/third_party/WebKit/Source/core/css/RuleFeature.cpp
+++ b/third_party/WebKit/Source/core/css/RuleFeature.cpp
@@ -148,6 +148,7 @@ bool supportsInvalidation(CSSSelector::PseudoType type)
     case CSSSelector::PseudoFutureCue:
     case CSSSelector::PseudoPastCue:
     case CSSSelector::PseudoUnresolved:
+    case CSSSelector::PseudoDefined:
     case CSSSelector::PseudoContent:
     case CSSSelector::PseudoHost:
     case CSSSelector::PseudoShadow:
@@ -345,6 +346,7 @@ InvalidationSet* RuleFeatureSet::invalidationSetForSelector(const CSSSelector& s
         case CSSSelector::PseudoInRange:
         case CSSSelector::PseudoOutOfRange:
         case CSSSelector::PseudoUnresolved:
+        case CSSSelector::PseudoDefined:
             return &ensurePseudoInvalidationSet(selector.getPseudoType(), type);
         default:
             break;