* lisp/pcomplete.el: Require comint.
(pcomplete--common-suffix): Remove.
(pcomplete--common-quoted-suffix): Use comint--common-suffix instead.
(pcomplete--table-subvert): Sync with comint--table-subvert.
(pcomplete--entries): Use comint-completion-file-name-table.
* lisp/comint.el (comint-unquote-filename): Simplify.
(comint-completion-file-name-table): New function.
(comint--complete-file-name-data): Use it.
* src/dired.c (file_name_completion): Don't expand file name.
(Ffile_name_completion, Ffile_name_all_completions): Expand file name
before checking file name handler.