Merge "Message: Throw if given invalid serialized data"

diff --combined includes/Message.php
index f9d1cce,7dd22c7..15d9786
--- 1/includes/Message.php
--- 2/includes/Message.php
+++ b/includes/Message.php
@@@ -290,7 -290,6 +290,7 @@@ class Message implements MessageSpecifi
                        'format' => $this->format,
                        'useDatabase' => $this->useDatabase,
                        'title' => $this->title,
 +                      'titlestr' => $this->title ? $this->title->getFullText() : null,
                ] );
        }
  
@@@ -301,6 -300,10 +301,10 @@@
         */
        public function unserialize( $serialized ) {
                $data = unserialize( $serialized );
+               if ( !is_array( $data ) ) {
+                       throw new InvalidArgumentException( __METHOD__ . ': Invalid serialized data' );
+               }
+ 
                $this->interface = $data['interface'];
                $this->key = $data['key'];
                $this->keysToTry = $data['keysToTry'];
@@@ -308,15 -311,7 +312,15 @@@
                $this->format = $data['format'];
                $this->useDatabase = $data['useDatabase'];
                $this->language = $data['language'] ? Language::factory( $data['language'] ) : false;
 -              $this->title = $data['title'];
 +
 +              if ( isset( $data['titlestr'] ) ) {
 +                      $this->title = Title::newFromText( $data['titlestr'] );
 +              } elseif ( isset( $data['title'] ) && $data['title'] instanceof Title ) {
 +                      // Old serializations from before December 2018
 +                      $this->title = $data['title'];
 +              } else {
 +                      $this->title = null; // Explicit for sanity
 +              }
        }
  
        /**