Fix a deprecation warning that occurs when saving a wiki page, makes sure paging filter preserved when searching fro wiki pages, a=chris

diff --git a/src/controllers/components/SocialComponent.php b/src/controllers/components/SocialComponent.php
index 71142a6d5..3c6fb9594 100644
--- a/src/controllers/components/SocialComponent.php
+++ b/src/controllers/components/SocialComponent.php
@@ -4164,6 +4164,7 @@ EOD;
                     $head_vars['page_type'] != 'standard')) {
                     $page = $head_string . "END_HEAD_VARS" . $page;
                 }
+                $page_info ??= [];
                 $page_info['ID'] = $group_model->setPageName($user_id,
                     $group_id, $page_name, $page,
                     $data['CURRENT_LOCALE_TAG'], $edit_reason,
diff --git a/src/views/elements/WikiElement.php b/src/views/elements/WikiElement.php
index 084cdb858..830f59f69 100644
--- a/src/views/elements/WikiElement.php
+++ b/src/views/elements/WikiElement.php
@@ -1601,6 +1601,9 @@ class WikiElement extends Element implements CrawlConstants
             $controller, $group_id)) . $token_string . "&arg=edit";
         $paging_query = htmlentities(B\wikiUrl("pages", true, $controller,
             $group_id)) . $token_string;
+        if (!empty($data['FILTER'])) {
+            $paging_query .= "&filter=" . $data['FILTER'];
+        }
         ?><h2 class="page-list-header-footer"><?=
             tl("wiki_element_wiki_create_find", $data["GROUP"]["GROUP_NAME"])
         ?></h2><?php