Warning about unsafe debugging library appears too late

1. Open a QML project.
2. Open the project's build settings. Make sure the QML debugging library was built.
   Creator displays a warning that linking the library is unsafe.
3. Uncheck "Link QML debugging library".
   While the warning is still being displayed, Creator asks if it should rebuild the project. Then the warning disappears.
4. Check "Link QML debugging library".
   The warning will not be displayed until the user made their decision.

Instead, the warning should appear immediately because the user should know this before deciding for or against a rebuild.