Remove unused widget handler overrides

fpdfsdk/formfiller/cffl_listbox.cpp

Index: fpdfsdk/formfiller/cffl_listbox.cpp
diff --git a/fpdfsdk/formfiller/cffl_listbox.cpp b/fpdfsdk/formfiller/cffl_listbox.cpp
index e4ea65b846341a35ce7cf3f89be868a92bb55aa6..d8331e5027a828536dbe25dc9b74d84db8a696d1 100644
--- a/fpdfsdk/formfiller/cffl_listbox.cpp
+++ b/fpdfsdk/formfiller/cffl_listbox.cpp
@@ -164,10 +164,6 @@ void CFFL_ListBox::GetActionData(CPDFSDK_PageView* pPageView,
   }
 }
 
-void CFFL_ListBox::SetActionData(CPDFSDK_PageView* pPageView,
-                                 CPDF_AAction::AActionType type,
-                                 const PDFSDK_FieldAction& fa) {}
-
 void CFFL_ListBox::SaveState(CPDFSDK_PageView* pPageView) {
   ASSERT(pPageView);