applet: chown each notified problem before reporting it

Not chowing all directories leads to stealing of koops problems and dump
dir stealing is obsolete because:
  - stolen directories are omitted in local duplicates search
  - root cannot seen those directories

Kernel oops problems are not problems of another user, they are rather
system problems. Koops problems are readable by all users but are not
writable. Fortunately koops directories can be chowned by all users
without providing any credentials.

Resolves #1084027

Chowing problem directories runs in abrt-dbus which shows an
authorization dialogue.

Signed-off-by: Jakub Filak <jfilak@redhat.com>