Rename url-button-google-url

* lisp/erc/erc-button.el (erc-button-search-url): Renamed from
url-button-google-url (bug#25717).  Suggested by Andrew Robbins.
(erc-button-alist): Use it.

etc/NEWS

@@ -210,6 +210,12 @@ concept index in the Gnus manual for the `match-list' entry.
 +++
 *** nil is no longer an allowed value for `mm-text-html-renderer'.
 
+** erc
+
+---
+*** `erc-button-google-url' has been renamed `erc-button-search-url'
+and its value has been changed to Duck Duck Go.
+
 ** eww/shr
 
 *** When opening external links in eww/shr (typically with the

lisp/erc/erc-button.el

@@ -121,12 +121,16 @@ longer than `erc-fill-column'."
   :group 'erc-button
   :type 'string)
 
-(defcustom erc-button-google-url "http://www.google.com/search?q=%s"
+(defcustom erc-button-search-url "http://duckduckgo.com/?q=%s"
   "URL used to browse Google search references.
 %s is replaced by the search string."
+  :version "27.1"
   :group 'erc-button
   :type 'string)
 
+(define-obsolete-variable-alias 'erc-button-google-url
+  'erc-button-search-url "27.1")
+
 (defcustom erc-button-alist
   ;; Since the callback is only executed when the user is clicking on
   ;; a button, it makes no sense to optimize performance by
@@ -148,7 +152,7 @@ longer than `erc-fill-column'."
     ("Lisp:\\([a-zA-Z.+-]+\\)" 0 t erc-browse-emacswiki-lisp 1)
     ("\\bGoogle:\\([^ \t\n\r\f]+\\)"
      0 t (lambda (keywords)
-           (browse-url (format erc-button-google-url keywords)))
+           (browse-url (format erc-button-search-url keywords)))
      1)
     ("\\brfc[#: ]?\\([0-9]+\\)"
      0 t (lambda (num)