location: don't log critical warnings for CANCELLED errors

These are expected when switching language.
account: don't double-unref GClosure

gtk_accel_group_connect() calls g_closure_sink() on the passed-in
GClosure, so calling g_closure_unref() here is wrong as it will lead to
a double unref. Spotted with valgrind.
language: plug a memory leak
location: plug memory leak
location: plug a memory leak
account: plug some memory leaks
Merge pull request #75 from endlessm/shell/4323

Shell/4323