* eshell/em-unix.el (top): Require 'esh-opt and 'pcomplete.
(eshell/su, eshell/sudo): Require 'tramp. Fix problems reading
arguments. Expand `default-directory'.
* net/tramp.el (tramp-handle-file-remote-p): Expand FILENAME for
the benefit of returning an expanded localname.
(tramp-tramp-file-p): Handle the case NAME is not a string.