load-library, locate-library: Use read-library-name

* lisp/emacs-lisp/find-func.el (read-library-name): Add autoload
cookie.
* lisp/files.el (load-library)
* lisp/subr.el (locate-library): Use 'read-library-name' when called
interactively. (bug#6652 bug#6679)

lisp/emacs-lisp/find-func.el

@@ -279,6 +279,7 @@ Interactively, prompt for LIBRARY using the one at or near point."
       (switch-to-buffer (find-file-noselect (find-library-name library)))
     (run-hooks 'find-function-after-hook)))
 
+;;;###autoload
 (defun read-library-name ()
   "Read and return a library name, defaulting to the one near point.
 

lisp/files.el

@@ -1103,12 +1103,7 @@ well as `load-file-rep-suffixes').
 
 See Info node `(emacs)Lisp Libraries' for more details.
 See `load-file' for a different interface to `load'."
-  (interactive
-   (let (completion-ignored-extensions)
-     (list (completing-read "Load library: "
-                            (apply-partially 'locate-file-completion-table
-                                             load-path
-                                             (get-load-suffixes))))))
+  (interactive (list (read-library-name)))
   (load library))
 
 (defun file-remote-p (file &optional identification connected)

lisp/subr.el

@@ -2301,12 +2301,7 @@ is used instead of `load-path'.
 When called from a program, the file name is normally returned as a
 string.  When run interactively, the argument INTERACTIVE-CALL is t,
 and the file name is displayed in the echo area."
-  (interactive (list (completing-read "Locate library: "
-				      (apply-partially
-                                       'locate-file-completion-table
-                                       load-path (get-load-suffixes)))
-		     nil nil
-		     t))
+  (interactive (list (read-library-name) nil nil t))
   (let ((file (locate-file library
 			   (or path load-path)
 			   (append (unless nosuffix (get-load-suffixes))