Move ERC's core dependencies to separate file

Move ERC's core dependencies to separate file

Asking people to order require's is about as effective
as asking kids to keep off the grass.

* lisp/erc/erc-backend.el (erc--target, erc-auto-query,
erc-channel-list, erc-channel-users, erc-default-nicks,
erc-default-recipients, erc-format-nick-function,
erc-format-query-as-channel-p, erc-hide-prompt, erc-input-marker,
erc-insert-marker, erc-invitation, erc-join-buffer,
erc-kill-buffer-on-part, erc-kill-server-buffer-on-quit, erc-log-p,
erc-minibuffer-ignored, erc-networks--id, erc-nick,
erc-nick-change-attempt-count, erc-prompt-for-channel-key,
erc-prompt-hidden, erc-reuse-buffers, erc-verbose-server-ping,
erc-whowas-on-nosuchnick): Forward-declare variables.
(erc--open-target, erc--target-from-string, erc-active-buffer,
erc-add-default-channel, erc-banlist-update, erc-buffer-filter,
erc-buffer-list-with-nick, erc-channel-begin-receiving-names,
erc-channel-end-receiving-names, erc-channel-p,
erc-channel-receive-names, erc-cmd-JOIN, erc-connection-established,
erc-current-nick, erc-current-nick-p, erc-current-time,
erc-default-target, erc-delete-default-channel,
erc-display-error-notice, erc-display-server-message,
erc-emacs-time-to-erc-time, erc-format-message,
erc-format-privmessage, erc-get-buffer, erc-handle-login,
erc-handle-user-status-change, erc-ignored-reply-p,
erc-ignored-user-p, erc-is-message-ctcp-and-not-action-p,
erc-is-message-ctcp-p, erc-log-irc-protocol, erc-login,
erc-make-notice, erc-network, erc-networks--id-given,
erc-networks--id-reload, erc-nickname-in-use, erc-parse-user,
erc-process-away, erc-process-ctcp-query, erc-query-buffer-p,
erc-remove-channel-member, erc-remove-channel-users, erc-remove-user,
erc-sec-to-time, erc-server-buffer, erc-set-active-buffer,
erc-set-current-nick, erc-set-modes, erc-time-diff, erc-trim-string,
erc-update-mode-line, erc-update-mode-line-buffer,
erc-wash-quit-reason, erc-display-message, erc-get-buffer-create,
erc-process-ctcp-reply, erc-update-channel-topic, erc-update-modes,
erc-update-user-nick, erc-open, erc-update-channel-member):
Forward-declare functions.
(erc-response): Move to lisp/erc/erc-common.el.
(erc-compat--with-memoization): Use "erc-compat-" prefixed macro.

* lisp/erc/erc-common.el: New file.  Change indentation for
`erc-with-all-buffers-of-server' from 1 to 2.

* lisp/erc/erc-compat.el (erc-compat--with-memoization): Migrate macro
from `erc-backend' and rename.

* lisp/erc/erc-goodies.el: Require `erc-common' instead of `erc'.
(erc-controls-highlight-regexp, erc-controls-remove-regexp,
erc-input-marker, erc-insert-marker, erc-server-process, erc-modules,
erc-log-p): Forward declare variables.
(erc-buffer-list, erc-error, erc-extract-command-from-line):
Forward-declare functions.

* lisp/erc/erc-networks.el (erc--target, erc-insert-marker,
erc-kill-buffer-hook, erc-kill-server-hook, erc-modules,
erc-rename-buffers, erc-reuse-buffers, erc-server-announced-name,
erc-server-connected, erc-server-parameters, erc-server-process,
erc-session-server): Forward declare variables.
(erc--default-target, erc--get-isupport-entry, erc-buffer-filter,
erc-current-nick, erc-display-error-notice, erc-error, erc-get-buffer,
erc-server-buffer, erc-server-process-alive): Forward-declare
functions.
(erc-obsolete-var): Also suppress free-variable warnings.

* lisp/erc/erc.el: Require `erc-networks', `erc-goodies', and
`erc-backend' at top of file.  Don't require `erc-compat'.
(erc--server-last-reconnect-count, erc--server-reconnecting,
erc-channel-members-changed-hook, erc-network, erc-networks--id,
erc-server-367-functions, erc-server-announced-name,
erc-server-connect-function, erc-server-connected,
erc-server-current-nick, erc-server-lag, erc-server-last-sent-time,
erc-server-process, erc-server-quitting, erc-server-reconnect-count,
erc-server-reconnecting, erc-session-client-certificate,
erc-session-connector, erc-session-port, erc-session-server,
erc-session-user-full-name) Remove superfluous forward declarations.
(erc-message-parsed, tabbar--local-hlf, motif-version-string):
Relocate forward declares to central location.
(erc-session-password): Move to `erc-backend'.
(erc-downcase, erc-with-server-buffer, erc-server-user,
erc-channel-user, erc-get-channel-user, erc-get-server-user): Move to
lisp/erc/erc-common.el.
(erc-add-server-user, erc-remove-server-user,
erc-channel-user-owner-p, erc-channel-user-admin-p,
erc-channel-user-op-p, erc-channel-user-halfop-p,
erc-channel-user-voice-p): Convert from inline functions to normal
functions.
(define-erc-module, erc--target, erc--target-channel,
erc--target-channel-local, erc-log, erc-log-aux, erc-with-buffer,
erc-with-all-buffers-of-server): Move to lisp/erc/erc-common.el.
(erc-channel-members-changed-hook): Relocate option to avoid compiler
warning.
(erc-input, erc--input-split): Move to lisp/erc/erc-common.el.
(erc-controls-strip): Remove forward declaration temporarily until
this file stops requiring `erc-goodies'.

* test/lisp/erc/erc-networks-tests.el: Require `erc' instead of
`erc-networks'.
* test/lisp/erc/erc.el (erc--meta--backend-dependencies): Remove
obsolete test.  Don't require `erc-networks'. Bug#56340.