Implement ::shadow pseudo element and replace /shadow/ with ::shadow.

Source/core/css/CSSSelector.h

 /*
  * Copyright (C) 1999-2003 Lars Knoll (knoll@kde.org)
  *               1999 Waldo Bastian (bastian@kde.org)
  * Copyright (C) 2004, 2006, 2007, 2008, 2009, 2010, 2013 Apple Inc. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
@@ skipping 110 matching lines @@
             End, // css3: E[foo$="bar"]
             PagePseudoClass // ??
         };
 
         enum Relation {
             Descendant = 0, // "Space" combinator
             Child, // > combinator
             DirectAdjacent, // + combinator
             IndirectAdjacent, // ~ combinator
             SubSelector, // "No space" combinator
-            ShadowPseudo, // Special case of shadow DOM pseudo elements
-            // FIXME: implement named combinator (i.e. named relation) and
-            // replace the following /shadow/ and /shadow-deep/ with the implementation.
-            Shadow, // /shadow/ combinator
-            ShadowDeep, // /shadow-deep/ combinator
+            ShadowPseudo, // Special case of shadow DOM pseudo elements / shadow pseudo element

[dglazkov, 2014/03/25 17:10:53]

This needs to be renamed to CustomPseudoElement or something, now that we have
an actual shadow pseudo :)

[tasak, 2014/03/26 11:01:46]

The actual shadow pseudo uses this relation, because, for example, div::shadow >
div" is converted to "div <==ShadowPseudo== ::shadow <==Child== div".

SelectorChecker uses "ShadowPseudo" to walk up from "::shadow"(shadow root) to
"div"(shadow host), because shadow roots are not elements.

+            ShadowDeep // /shadow-deep/ combinator
         };
 
         enum PseudoType {
             PseudoNotParsed = 0,
             PseudoUnknown,
             PseudoEmpty,
             PseudoFirstChild,
             PseudoFirstOfType,
             PseudoLastChild,
             PseudoLastOfType,
@@ skipping 65 matching lines @@
             PseudoOutOfRange,
             PseudoUserAgentCustomElement,
             PseudoWebKitCustomElement,
             PseudoCue,
             PseudoFutureCue,
             PseudoPastCue,
             PseudoDistributed,
             PseudoUnresolved,
             PseudoContent,
             PseudoHost,
-            PseudoAncestor
+            PseudoAncestor,
+            PseudoShadow
         };
 
         enum OptionalPseudoTypeRequirements {
             // 0 is used to mean "no requirements".
             RequiresShadowDOM = 1
         };
 
         enum MarginBoxType {
             TopLeftCornerMarginBox,
             TopLeftMarginBox,
@@ skipping 55 matching lines @@
         bool matchNth(int count) const;
 
         bool matchesPseudoElement() const;
         bool isUnknownPseudoElement() const;
         bool isCustomPseudoElement() const;
         bool isDirectAdjacentSelector() const { return m_relation == DirectAdjacent; }
         bool isSiblingSelector() const;
         bool isAttributeSelector() const;
         bool isDistributedPseudoElement() const;
         bool isContentPseudoElement() const;
+        bool isShadowPseudoElement() const;
         bool isHostPseudoClass() const;
 
         // FIXME: selectors with no tagHistory() get a relation() of Descendant. It should instead be
         // None.
         Relation relation() const { return static_cast<Relation>(m_relation); }
 
         bool isLastInSelectorList() const { return m_isLastInSelectorList; }
         void setLastInSelectorList() { m_isLastInSelectorList = true; }
         bool isLastInTagHistory() const { return m_isLastInTagHistory; }
         void setNotLastInTagHistory() { m_isLastInTagHistory = false; }
@@ skipping 115 matching lines @@
 inline bool CSSSelector::isDistributedPseudoElement() const
 {
     return m_match == PseudoElement && pseudoType() == PseudoDistributed;
 }
 
 inline bool CSSSelector::isContentPseudoElement() const
 {
     return m_match == PseudoElement && pseudoType() == PseudoContent;
 }
 
+inline bool CSSSelector::isShadowPseudoElement() const
+{
+    return m_match == PseudoElement && pseudoType() == PseudoShadow;
+}
+
 inline void CSSSelector::setValue(const AtomicString& value)
 {
     ASSERT(m_match != Tag);
     ASSERT(m_pseudoType == PseudoNotParsed);
     // Need to do ref counting manually for the union.
     if (m_hasRareData) {
         m_data.m_rareData->m_value = value;
         return;
     }
     if (m_data.m_value)
@@ skipping 78 matching lines @@
     if (m_hasRareData)
         return m_data.m_rareData->m_value;
     // AtomicString is really just a StringImpl* so the cast below is safe.
     // FIXME: Perhaps call sites could be changed to accept StringImpl?
     return *reinterpret_cast<const AtomicString*>(&m_data.m_value);
 }
 
 } // namespace WebCore
 
 #endif // CSSSelector_h