Use union types for HTMLSelectElement.add()'s arguments

Source/core/html/HTMLOptionsCollection.h

Index: Source/core/html/HTMLOptionsCollection.h
diff --git a/Source/core/html/HTMLOptionsCollection.h b/Source/core/html/HTMLOptionsCollection.h
index 86a2c8c9e2841d8ec306a5f83907f4102738b5f1..a112371f0ecdde8d86c7a194589e65f55c0ac5d5 100644
--- a/Source/core/html/HTMLOptionsCollection.h
+++ b/Source/core/html/HTMLOptionsCollection.h
@@ -30,6 +30,8 @@
 namespace blink {
 
 class ExceptionState;
+class HTMLOptionElementOrHTMLOptGroupElement;
+class HTMLElementOrLong;
 class NodeListOrElement;
 
 class HTMLOptionsCollection final : public HTMLCollection {
@@ -39,8 +41,7 @@ public:
 
     HTMLOptionElement* item(unsigned offset) const { return toHTMLOptionElement(HTMLCollection::item(offset)); }
 
-    void add(PassRefPtrWillBeRawPtr<HTMLOptionElement>, ExceptionState&);
-    void add(PassRefPtrWillBeRawPtr<HTMLOptionElement>, int index, ExceptionState&);
+    void add(const HTMLOptionElementOrHTMLOptGroupElement&, const HTMLElementOrLong&, ExceptionState&);
     void remove(int index);
 
     int selectedIndex() const;