Comment 3 for bug 268956

Unless I'm doing something wrong, it's not there:

$ grep -r "all/all" /usr/share/applications ~/.local
$ grep -r "uri/mms" /usr/share/applications ~/.local
$ grep -r "uri/rtsp" /usr/share/applications ~/.local
$ grep -r "fonts/package" /usr/share/applications ~/.local
$ grep -r "interface/x-winamp-skin" /usr/share/applications ~/.local
$ grep -r "uri/pnm" /usr/share/applications ~/.local

However,

$ sudo update-mime-database /usr/share/mime
Unknown media type in type 'all/all'

Unknown media type in type 'all/allfiles'

Unknown media type in type 'uri/mms'

Unknown media type in type 'uri/mmst'

Unknown media type in type 'uri/mmsu'

Unknown media type in type 'uri/pnm'

Unknown media type in type 'uri/rtspt'

Unknown media type in type 'uri/rtspu'

Unknown media type in type 'fonts/package'

Unknown media type in type 'interface/x-winamp-skin'

$ grep -r "interface/x-winamp-skin" /usr/share/mime
/usr/share/mime/globs:interface/x-winamp-skin:*.wsz
/usr/share/mime/types:interface/x-winamp-skin
/usr/share/mime/packages/kde.xml: <mime-type type="interface/x-winamp-skin">
/usr/share/mime/subclasses:interface/x-winamp-skin application/zip
/usr/share/mime/globs2:50:interface/x-winamp-skin:*.wsz
/usr/share/mime/interface/x-winamp-skin.xml:<mime-type xmlns="http://www.freedesktop.org/standards/shared-mime-info" type="interface/x-winamp-skin">

$ grep -r "uri/mms" /usr/share/mime
/usr/share/mime/uri/mmst.xml:<mime-type xmlns="http://www.freedesktop.org/standards/shared-mime-info" type="uri/mmst">
/usr/share/mime/uri/mmsu.xml:<mime-type xmlns="http://www.freedesktop.org/standards/shared-mime-info" type="uri/mmsu">
/usr/share/mime/uri/mms.xml:<mime-type xmlns="http://www.freedesktop.org/standards/shared-mime-info" type="uri/mms">
/usr/share/mime/types:uri/mms
/usr/share/mime/types:uri/mmst
/usr/share/mime/types:uri/mmsu
/usr/share/mime/packages/kde.xml: <mime-type type="uri/mms">
/usr/share/mime/packages/kde.xml: <mime-type type="uri/mmst">
/usr/share/mime/packages/kde.xml: <mime-type type="uri/mmsu">

$ grep -r "all/all" /usr/share/mime
/usr/share/mime/all/all.xml:<mime-type xmlns="http://www.freedesktop.org/standards/shared-mime-info" type="all/all">
/usr/share/mime/all/allfiles.xml:<mime-type xmlns="http://www.freedesktop.org/standards/shared-mime-info" type="all/allfiles">
/usr/share/mime/types:all/all
/usr/share/mime/types:all/allfiles
/usr/share/mime/packages/kde.xml: <mime-type type="all/all">
/usr/share/mime/packages/kde.xml: <mime-type type="all/allfiles">

$ dpkg-query -S /usr/share/mime/packages/kde.xml
kdelibs5-data: /usr/share/mime/packages/kde.xml

$ aptitude show kdelibs5-data
Package: kdelibs5-data
State: installed
Automatically installed: no
Version: 4:4.1.1+really4.1.1-0ubuntu3
[snip]