Let unresolved custom element go through CustomElementCallbackQueue.

Source/core/dom/custom/CustomElementResolutionStep.h

Index: Source/core/dom/custom/CustomElementResolutionStep.h
diff --git a/Source/core/dom/custom/CustomElementBaseElementQueue.h b/Source/core/dom/custom/CustomElementResolutionStep.h
similarity index 69%
copy from Source/core/dom/custom/CustomElementBaseElementQueue.h
copy to Source/core/dom/custom/CustomElementResolutionStep.h
index 78882aa3e0aeec12fa0c5a5336441ff08bd2af09..9f0abbec6eb3781e3c76b41835604e1ba20375cb 100644
--- a/Source/core/dom/custom/CustomElementBaseElementQueue.h
+++ b/Source/core/dom/custom/CustomElementResolutionStep.h
@@ -28,31 +28,32 @@
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
-#ifndef CustomElementBaseElementQueue_h
-#define CustomElementBaseElementQueue_h
+#ifndef CustomElementResolutionStep_h
+#define CustomElementResolutionStep_h
 
-#include "wtf/Vector.h"
+#include "core/dom/custom/CustomElementDescriptor.h"
+#include "core/dom/custom/CustomElementProcessingStep.h"
+#include "wtf/PassOwnPtr.h"
+#include "wtf/text/AtomicString.h"
 
 namespace WebCore {
 
-class CustomElementCallbackQueue;
-
-class CustomElementBaseElementQueue {
-    WTF_MAKE_NONCOPYABLE(CustomElementBaseElementQueue);
+class CustomElementResolutionStep : public CustomElementProcessingStep {
+    WTF_MAKE_NONCOPYABLE(CustomElementResolutionStep);
 public:
-    CustomElementBaseElementQueue() : m_inDispatch(false) { }
+    static PassOwnPtr<CustomElementResolutionStep> create(const CustomElementDescriptor&);
 
-    bool isEmpty() const { return m_queue.isEmpty(); }
-    void enqueue(CustomElementCallbackQueue*);
+protected:
+    CustomElementResolutionStep(const CustomElementDescriptor& descriptor)
+        : m_descriptor(descriptor)
+    { }
 
-    typedef int ElementQueue;
-    bool dispatch(ElementQueue baseQueueId);
+    virtual void dispatch(Element*) OVERRIDE;
 
 private:
-    bool m_inDispatch;
-    Vector<CustomElementCallbackQueue*> m_queue;
+    CustomElementDescriptor m_descriptor;
 };
 
 }
 
-#endif // CustomElementBaseElementQueue_h
+#endif // CustomElementResolutionStep_h