(completion-all-completions-with-base-size): Remove.

(completion-all-completions-with-base-size): Remove.
(completion-all-completions): Don't set it.
(completion-table-with-context, completion--file-name-table):
Don't add base-size in last cdr.
(completion-hilit-commonality): Add argument `base-size'.
(display-completion-list, completion-emacs21-all-completions)
(completion-emacs22-all-completions, completion-basic-all-completions):
Provide it.
(completion-pcm--all-completions): Don't need to remove the base-size
in last-cdr any more.