PixelPaint: Propagate errors from making tool property widgets

Author: https://github.com/krkk
Commit: be717edd33
Pull-request: https://github.com/SerenityOS/serenity/pull/17445
Reviewed-by: https://github.com/AtkinsSJ ✅

Userland/Applications/PixelPaint/ToolPropertiesWidget.h

@@ -32,6 +32,7 @@ private:
     Tool* m_active_tool { nullptr };
     RefPtr<GUI::StackWidget> m_tool_widget_stack;
     RefPtr<GUI::Widget> m_blank_widget;
+    RefPtr<GUI::Label> m_error_label;
     GUI::Widget* m_active_tool_widget { nullptr };
 };