Handle and match new "group" entry in addressbook.

* helm-bookmark.el (helm-bookmark--addressbook-search-mail): Renamed
from helm-bookmark--addressbook-search-fn.
(helm-bookmark--addressbook-search-group): New.
(helm-bookmark-addressbook-class): Add group prop at initialization and
add one more fn to search fns.

helm-bookmark.el

@@ -519,7 +519,7 @@ than `w3m-browse-url' use it."
 ;;; Addressbook.
 ;;
 ;;
-(defun helm-bookmark-addressbook-search-fn (pattern)
+(defun helm-bookmark--addressbook-search-mail (pattern)
   (helm-awhile (next-single-property-change (point) 'email)
     (goto-char it)
     (end-of-line)
@@ -530,17 +530,29 @@ than `w3m-browse-url' use it."
       (cl-return
        (+ (point) (match-end 0))))))
 
+(defun helm-bookmark--addressbook-search-group (pattern)
+  (helm-awhile (next-single-property-change (point) 'group)
+    (goto-char it)
+    (end-of-line)
+    (when (string-match pattern
+                        (get-text-property
+                         0 'group (buffer-substring
+                                   (point-at-bol) (point-at-eol))))
+      (cl-return
+       (+ (point) (match-end 0))))))
+
 (defclass helm-bookmark-addressbook-class (helm-source-in-buffer)
   ((init :initform (lambda ()
                      (require 'addressbook-bookmark nil t)
                      (bookmark-maybe-load-default-file)
                      (helm-init-candidates-in-buffer
                          'global
                        (cl-loop for b in (helm-bookmark-addressbook-setup-alist)
-                                collect (propertize
-                                         b 'email (bookmark-prop-get
-                                                   b 'email))))))
-   (search :initform 'helm-bookmark-addressbook-search-fn)
+                                collect (propertize b
+                                                    'email (bookmark-prop-get b 'email)
+                                                    'group (bookmark-prop-get b 'group))))))
+   (search :initform '(helm-bookmark--addressbook-search-group
+                       helm-bookmark--addressbook-search-mail))
    (persistent-action :initform
                       (lambda (candidate)
                         (let ((bmk (helm-bookmark-get-bookmark-from-name