[easytag/easytag-2-2] Fix an invalid read when reading MP4 cover art

[David King <davidk src gnome org>]

commit 7b727b30e88d249f34a276f2766d2876654c37e0
Author: David King <amigadave amigadave com>
Date:   Mon Oct 20 23:08:25 2014 +0100

    Fix an invalid read when reading MP4 cover art

 src/mp4_tag.cc |    3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)
---
diff --git a/src/mp4_tag.cc b/src/mp4_tag.cc
index efeaebd..3fa1a68 100644
--- a/src/mp4_tag.cc
+++ b/src/mp4_tag.cc
@@ -215,7 +215,8 @@ gboolean Mp4tag_Read_File_Tag (gchar *filename, File_Tag *FileTag)
     if (extra_items.contains ("covr"))
     {
         const TagLib::MP4::Item cover = extra_items["covr"];
-        const TagLib::MP4::CoverArt &art = cover.toCoverArtList ().front ();
+        const TagLib::MP4::CoverArtList covers = cover.toCoverArtList ();
+        const TagLib::MP4::CoverArt &art = covers.front ();
 
         FileTag->picture = Picture_Allocate ();