* lisp/emacs-lisp/package.el: Fix bug#16733 (again).

* lisp/emacs-lisp/package.el: Fix bug#16733 (again).
  (url-http-parse-response, url-http-end-of-headers, url-recreate-url)
  (url-http-target-url): Remove unused declarations.
  (package-handle-response): Remove.
  (package--with-work-buffer): Use url-insert-file-contents and simplify.
  (package--download-one-archive): Use current-buffer instead of
  dynamic binding of `buffer'.
  (describe-package-1): Do not decode readme-string.

* lisp/url/url-handlers.el (url-http-parse-response): Add autoload.
  (url-insert-file-contents): Signal file-error in case of HTTP error.