Codechange: use default dtor instead of empty (#10826)

src/widgets/dropdown_type.h

@@ -25,7 +25,7 @@ public:
 	bool masked; ///< Masked and unselectable item
 
 	DropDownListItem(int result, bool masked) : result(result), masked(masked) {}
-	virtual ~DropDownListItem() {}
+	virtual ~DropDownListItem() = default;
 
 	virtual bool Selectable() const { return false; }
 	virtual uint Height(uint width) const { return FONT_HEIGHT_NORMAL; }