Implement CSS parser part for ::slotted pseudo element

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

Index: third_party/WebKit/Source/core/css/CSSSelector.cpp
diff --git a/third_party/WebKit/Source/core/css/CSSSelector.cpp b/third_party/WebKit/Source/core/css/CSSSelector.cpp
index 24614344a7a7ddb492bd9433d31d07105abf8449..f5caef77aaf60270310f98345613bb7ba2d41903 100644
--- a/third_party/WebKit/Source/core/css/CSSSelector.cpp
+++ b/third_party/WebKit/Source/core/css/CSSSelector.cpp
@@ -264,6 +264,7 @@ PseudoId CSSSelector::pseudoId(PseudoType type)
     case PseudoFullScreenAncestor:
     case PseudoSpatialNavigationFocus:
     case PseudoListBox:
+    case PseudoSlotted:
         return NOPSEUDO;
     }
 
@@ -367,6 +368,7 @@ const static NameToPseudoStruct pseudoTypeWithArgumentsMap[] = {
 {"nth-last-child",   CSSSelector::PseudoNthLastChild},
 {"nth-last-of-type", CSSSelector::PseudoNthLastOfType},
 {"nth-of-type",      CSSSelector::PseudoNthOfType},
+{"slotted",          CSSSelector::PseudoSlotted},
 };
 
 class NameToPseudoCompare {
@@ -481,6 +483,7 @@ void CSSSelector::updatePseudoType(const AtomicString& value, bool hasArguments)
     case PseudoWebKitCustomElement:
     case PseudoContent:
     case PseudoShadow:
+    case PseudoSlotted:
         if (m_match != PseudoElement)
             m_pseudoType = PseudoUnknown;
         break;
@@ -725,6 +728,7 @@ String CSSSelector::selectorText(const String& rightSide) const
         case SubSelector:
             ASSERT_NOT_REACHED();
         case ShadowPseudo:
+        case ShadowSlot:
             return tagHistory->selectorText(str.toString() + rightSide);
         }
     }
@@ -795,6 +799,7 @@ static bool validateSubSelector(const CSSSelector* selector)
     case CSSSelector::PseudoNot:
     case CSSSelector::PseudoSpatialNavigationFocus:
     case CSSSelector::PseudoListBox:
+    case CSSSelector::PseudoSlotted:

[rune, 2016/01/15 11:01:16]

This method is used for validating selectors in <content select="...">. I doubt
PseudoSlotted should be allowed there?

[kochi, 2016/01/19 07:25:56]

Good catch.

It seems I mistakenly added this line.

This function should have returned false for pseudo elements
in another switch-case above
(case CSSSelector::PseudoElement: return false) already.

Removed this line.

         return true;
     default:
         return false;