Support indexed setter generation

Source/core/html/HTMLSelectElement.cpp

Index: Source/core/html/HTMLSelectElement.cpp
diff --git a/Source/core/html/HTMLSelectElement.cpp b/Source/core/html/HTMLSelectElement.cpp
index 77585bfd9bca30d165811d9dd4236d94547a6849..58c4768b92b47e35aac7d597bffe1037f31e1523 100644
--- a/Source/core/html/HTMLSelectElement.cpp
+++ b/Source/core/html/HTMLSelectElement.cpp
@@ -1570,4 +1570,14 @@ void HTMLSelectElement::finishParsingChildren()
     updateListItemSelectedStates();
 }
 
+bool HTMLSelectElement::anonymousIndexedSetter(unsigned index, PassRefPtr<HTMLOptionElement> value, bool isValueNull, bool isValueUndefined, ExceptionCode& ec)
+{
+    if (!value) {
+        ec = TYPE_MISMATCH_ERR;
+        return false;
+    }
+    setOption(index, value.get(), ec);
+    return true;
+}
+
 } // namespace