Avoid warnings in ObjectCache::newWANCacheFromParams if "channels" is not set"

Bug: T192473
Change-Id: I150eef62285e99fc1269a58fee3827e5fbb0537b

diff --git a/includes/objectcache/ObjectCache.php b/includes/objectcache/ObjectCache.php
index 67d2346..a6f55e6 100644 (file)
--- a/includes/objectcache/ObjectCache.php
+++ b/includes/objectcache/ObjectCache.php
@@ -337,9 +337,11 @@ class ObjectCache {
                $services = MediaWikiServices::getInstance();
 
                $erGroup = $services->getEventRelayerGroup();
-               foreach ( $params['channels'] as $action => $channel ) {
-                       $params['relayers'][$action] = $erGroup->getRelayer( $channel );
-                       $params['channels'][$action] = $channel;
+               if ( isset( $params['channels'] ) ) {
+                       foreach ( $params['channels'] as $action => $channel ) {
+                               $params['relayers'][$action] = $erGroup->getRelayer( $channel );
+                               $params['channels'][$action] = $channel;
+                       }
                }
                $params['cache'] = self::newFromParams( $params['store'] );
                if ( isset( $params['loggroup'] ) ) {