Handle application whose .desktop doesn't exist

[Zaedus]

An error is thrown when attempting to delete a web app whose .desktop doesn't exist anymore (for whatever reason). Additionally, if the desktop file doesn't exist, getting the app's icon is impossible, meaning the AppRow fails to load, meaning the the AppPage can't be shown, meaning no deletion. Do not ask how I managed to even attempt deletion given this fact...

There should be a default icon if we cannot load the actual icon, and deletion should probably check if the file exists before attempting an uninstall.

[Zaedus]

To follow up on this issue: When I uninstall the app (but keep the data) and then reinstall, everything is fine except all the desktop files have been removed. Having some kind of "doctor" dialog that warns you of the problem and gives the user a button which will fix it would be ideal since each desktop file requires user confirmation, and I'd imagine most would be confused at the unexplained multitude of prompts if it automatically went ahead and fixed it.

For those encountering this problem, the easiest way to get your launcher/.desktop file back is to change the name or icon since those require reinstalling it.