Sorted the data file content extents by ECMA-119 tree rather than

by the red-black tree which shall consolidate files with identical
source object. Discovered and repaired a flaw in transitivity of
iso_stream_cmp_ino().

libisofs/ecma119.h

@@ -702,6 +702,8 @@ struct ecma119_image
     /* tree of files sources */
     IsoRBTree *files;
 
+    struct iso_filesrc_list_item *ecma119_hidden_list;
+
     unsigned int checksum_idx_counter;
     void *checksum_ctx;
     off_t checksum_counter;