Revert "Use DOMSettableTokenList for {HTMLAnchorElement, HTMLAreaElement}.ping."

third_party/WebKit/Source/core/html/HTMLAnchorElement.h

Index: third_party/WebKit/Source/core/html/HTMLAnchorElement.h
diff --git a/third_party/WebKit/Source/core/html/HTMLAnchorElement.h b/third_party/WebKit/Source/core/html/HTMLAnchorElement.h
index deeae3f7a170723bbc249da1d3af7842fcb169c2..17161225c936aa4128728b58dca51fd4aa26b120 100644
--- a/third_party/WebKit/Source/core/html/HTMLAnchorElement.h
+++ b/third_party/WebKit/Source/core/html/HTMLAnchorElement.h
@@ -26,7 +26,6 @@
 
 #include "core/CoreExport.h"
 #include "core/HTMLNames.h"
-#include "core/dom/DOMSettableTokenList.h"
 #include "core/dom/DOMURLUtils.h"
 #include "core/dom/Document.h"
 #include "core/html/HTMLElement.h"
@@ -57,9 +56,8 @@ enum {
 //     RelationUp          = 0x00020000,
 };
 
-class CORE_EXPORT HTMLAnchorElement : public HTMLElement, public DOMURLUtils, public DOMSettableTokenListObserver {
+class CORE_EXPORT HTMLAnchorElement : public HTMLElement, public DOMURLUtils {
     DEFINE_WRAPPERTYPEINFO();
-    WILL_BE_USING_GARBAGE_COLLECTED_MIXIN(HTMLAnchorElement);
 public:
     static PassRefPtrWillBeRawPtr<HTMLAnchorElement> create(Document&);
 
@@ -88,10 +86,6 @@ public:
 
     void sendPings(const KURL& destinationURL) const;
 
-    DOMSettableTokenList* ping();
-
-    DECLARE_VIRTUAL_TRACE();
-
 protected:
     HTMLAnchorElement(const QualifiedName&, Document&);
 
@@ -117,13 +111,9 @@ private:
     InsertionNotificationRequest insertedInto(ContainerNode*) override;
     void handleClick(Event*);
 
-    // DOMSettableTokenListObserver
-    void valueChanged() override;
-
     uint32_t m_linkRelations;
     mutable LinkHash m_cachedVisitedLinkHash;
     bool m_wasFocusedByMouse;
-    RefPtrWillBeMember<DOMSettableTokenList> m_ping;
 };
 
 inline LinkHash HTMLAnchorElement::visitedLinkHash() const