Comment 2 for bug 1031753

StacktraceTop:
 g_str_hash (v=0x0) at /build/buildd/glib2.0-2.33.6/./glib/ghash.c:1730
 g_hash_table_lookup_node (hash_return=<synthetic pointer>, key=0x0, hash_table=0x7fba780044c0) at /build/buildd/glib2.0-2.33.6/./glib/ghash.c:401
 g_hash_table_lookup (hash_table=0x7fba780044c0, key=key@entry=0x0) at /build/buildd/glib2.0-2.33.6/./glib/ghash.c:1074
 check_ignore_next_update (fs=fs@entry=0xe0c030, queue_file=queue_file@entry=0xf53400) at tracker-miner-fs.c:1689
 item_queue_get_next_file (priority_out=<synthetic pointer>, source_file=<synthetic pointer>, file=<synthetic pointer>, fs=0xe0c030) at tracker-miner-fs.c:1815