[Oilpan] Prepare full definition of classes before using Member

third_party/WebKit/Source/core/html/HTMLSelectElement.cpp

Index: third_party/WebKit/Source/core/html/HTMLSelectElement.cpp
diff --git a/third_party/WebKit/Source/core/html/HTMLSelectElement.cpp b/third_party/WebKit/Source/core/html/HTMLSelectElement.cpp
index 845e3edcda546de10e9687183f5597f65f471676..458aac66214148ea95b3637837293e03db73bd21 100644
--- a/third_party/WebKit/Source/core/html/HTMLSelectElement.cpp
+++ b/third_party/WebKit/Source/core/html/HTMLSelectElement.cpp
@@ -1947,6 +1947,11 @@ void HTMLSelectElement::hidePopup()
         m_popup->hide();
 }
 
+PopupMenu* HTMLSelectElement::popup() const
+{
+    return m_popup.get();
+}
+
 void HTMLSelectElement::didRecalcStyle(StyleRecalcChange change)
 {
     HTMLFormControlElementWithState::didRecalcStyle(change);