MDL-31006 fix various notices in PHP54

PHP54 compatibility

Conflicts:

	lib/filterlib.php
	mod/feedback/lib.php
	report/participation/index.php

lib/blocklib.php

@@ -1676,7 +1676,7 @@ function generate_page_type_patterns($pagetype, $parentcontext = null, $currentc
 
     // Ensure that the * pattern is always available if editing block 'at distance', so
     // we always can 'bring back' it to the original context. MDL-30340
-    if ($currentcontext->id != $parentcontext->id && !isset($patterns['*'])) {
+    if ((!isset($currentcontext) or !isset($parentcontext) or $currentcontext->id != $parentcontext->id) && !isset($patterns['*'])) {
         // TODO: We could change the string here, showing its 'bring back' meaning
         $patterns['*'] = get_string('page-x', 'pagetype');
     }