Group Database backend must not gather user details itself but ask user

backends. This is a port to master from PR #7745

remove OC_GROUP_BACKEND_GET_DISPLAYNAME option for group backends

Conflicts:
	lib/private/group/backend.php

LDAP: getDisplayNamesInGroup is not an option for group backends anymore

Conflicts:
	apps/user_ldap/group_ldap.php
	apps/user_ldap/group_proxy.php

clean up group backends

Conflicts:
	lib/private/group/database.php

remove now unnecessary test

implement getDisplayNames in group manager

adjust user manager tests

test for group manager's displayNamesInGroup

trim must not be used in empty in PHP < 5.5

keep the constant to not provoke PHP warnings

Conflicts:
	lib/private/group/backend.php

1 files changed, 1 insertions, 5 deletions

diff --git a/lib/private/group/group.php b/lib/private/group/group.php
index 3efbb6e7023..7593bb68d1a 100644
--- a/lib/private/group/group.php
+++ b/lib/private/group/group.php
@@ -212,11 +212,7 @@ class Group {
 	public function searchDisplayName($search, $limit = null, $offset = null) {
 		$users = array();
 		foreach ($this->backends as $backend) {
-			if ($backend->implementsActions(OC_GROUP_BACKEND_GET_DISPLAYNAME)) {
-				$userIds = array_keys($backend->displayNamesInGroup($this->gid, $search, $limit, $offset));
-			} else {
-				$userIds = $backend->usersInGroup($this->gid, $search, $limit, $offset);
-			}
+			$userIds = $backend->usersInGroup($this->gid, $search, $limit, $offset);
 			$users = $this->getVerifiedUsers($userIds);
 			if (!is_null($limit) and $limit <= 0) {
 				return array_values($users);