Instead of using QProcess to determine the version number of the update-mime-database executable,

open it and read its contents directly to extract the version number. This should fix the freezing
issues exhibited in applications like VLC that block SIGCHLD, which QProcess needs to do its job.
See http://lists.kde.org/?t=129572447500001&r=1&w=2 for details on this issue.

BUG: 260719