Merge to XFA: Remove dead code that was reactivated when fixing overrides.

fpdfsdk/src/formfiller/FFL_FormFiller.cpp

Index: fpdfsdk/src/formfiller/FFL_FormFiller.cpp
diff --git a/fpdfsdk/src/formfiller/FFL_FormFiller.cpp b/fpdfsdk/src/formfiller/FFL_FormFiller.cpp
index 30a297dd68eba82f92ab55da14d28d7696ddaf2d..b6224294df48f846d2469c1d8017ba48e7e13c8f 100644
--- a/fpdfsdk/src/formfiller/FFL_FormFiller.cpp
+++ b/fpdfsdk/src/formfiller/FFL_FormFiller.cpp
@@ -602,8 +602,6 @@ IFX_SystemHandler* CFFL_FormFiller::GetSystemHandler() const {
   return m_pApp->GetSysHandler();
 }
 
-void CFFL_FormFiller::OnKeyStroke(FX_BOOL bKeyDown, FX_DWORD nFlag) {}
-
 void CFFL_FormFiller::EscapeFiller(CPDFSDK_PageView* pPageView,
                                    FX_BOOL bDestroyPDFWindow) {
   m_bValid = FALSE;