* lisp/simple.el (read-expression-map): Use completion-at-point.

* lisp/simple.el (read-expression-map): Use completion-at-point.
Move the declaration from C.
(read-minibuffer, eval-minibuffer): Move from C.
(completion-setup-function): Avoid minibuffer-completion-contents.
* src/minibuf.c (Fread_minibuffer, Feval_minibuffer): Move to Elisp.
(syms_of_minibuf): Adjust accodingly.
* src/lread.c (Fread):
* src/callint.c (Fcall_interactively): Adjust calls accordingly.