Only generate fake focus lost events when using the generic implementation

aegisub/src/auto4_lua_dialog.cpp

@@ -351,8 +351,10 @@ namespace Automation4 {
 				bool TransferFromWindow()
 				{
 					wxSpinCtrlDouble *ctrl = static_cast<wxSpinCtrlDouble*>(GetWindow());
+#ifndef wxHAS_NATIVE_SPINCTRLDOUBLE
 					wxFocusEvent evt;
 					ctrl->OnTextLostFocus(evt);
+#endif
 					*value = ctrl->GetValue();
 					return true;
 				}