When a user tries to send a (group) private message to a deactivated
user, a compose error is displayed.
Fixes#13766.
Co-authored-by: Signior-X <b19188@students.iitmandi.ac.in>
This is pretty much a verbatim code move,
except that I inlined noop and reset_jquery
in the new file.
Also, in the last test, I no longer reset
the compose state.