bash_completion: make export fall back to tags when there's no mq patch applied

contrib/bash_completion

@@ -193,7 +193,13 b' shopt -s extglob'
 	help)
 	    _hg_commands
 	;;
-	export|manifest|update)
+	export)
+	    if _hg_ext_mq_patchlist qapplied && [ "${COMPREPLY[*]}" ]; then
+		return 0
+	    fi
+	    _hg_tags
+	;;
+	manifest|update)
 	    _hg_tags
 	;;
 	pull|push|outgoing|incoming)
@@ -318,11 +324,6 b' complete -o bashdefault -o default -F _h'
     COMPREPLY=(${COMPREPLY[@]:-} $(compgen -W '$files' -- "$cur"))
 }
 
-_hg_cmd_export()
-{
-    _hg_ext_mq_patchlist qapplied
-}
-
 
 # hbisect
 _hg_cmd_bisect()