Merge "Add pages with ignored restricted {{DISPLAYTITLE}}s to a tracking category"

diff --combined includes/parser/CoreParserFunctions.php
index d49c4e4,d8bd42e..6b847e5
--- 1/includes/parser/CoreParserFunctions.php
--- 2/includes/parser/CoreParserFunctions.php
+++ b/includes/parser/CoreParserFunctions.php
@@@ -460,6 -460,7 +460,7 @@@ class CoreParserFunctions 
                                return '';
                        }
                } else {
+                       $parser->addTrackingCategory( 'restricted-displaytitle-ignored' );
                        $converter = $parser->getConverterLanguage()->getConverter();
                        return '<span class="error">' .
                                wfMessage( 'restricted-displaytitle',
@@@ -774,10 -775,6 +775,10 @@@
                // fetch revision from cache/database and return the value
                $rev = self::getCachedRevisionObject( $parser, $title );
                $length = $rev ? $rev->getSize() : 0;
 +              if ( $length === null ) {
 +                      // We've had bugs where rev_len was not being recorded for empty pages, see T135414
 +                      $length = 0;
 +              }
                return self::formatRaw( $length, $raw );
        }