xdg-mime: no error/logs when parsing .desktop file failed

xdg-mime doesn't provide any info on if the mime types failed to be set or not.

How to repro:

1. Create a corrupt .desktop file: cat "[Desktop Entry]" > ~/.local/share/applications/test.desktop
2. Set the mime type: xdg-mime default test.desktop inode/directory
3. The mime type failed to set, but no errors or logs were given. xdg-mime query default inode/directory still shows the previous .desktop entry that was last set.