crash on broken mp3

[easytag-ML malenki ch]

Not sure if you want to fix this but for my peace of mind I report
it. :)

I record web streams from radio stations. This time I got a broken file
which I only realized when easytag crashed on it as soon as it tries
to write anything.

You can find the file here:
https://malenki.ch/d/bugs/mdr_Figaro_Figarinos_Kinderhoerspiel_2016-03-20_crashes_easytag_2.4.2.mp3

This is what gdb reports:

[Thread debugging using libthread_db enabled]
Using host libthread_db library
"/lib/x86_64-linux-gnu/libthread_db.so.1". [New Thread 0x7fffed1e1700
(LWP 14767)] [New Thread 0x7fffec9e0700 (LWP 14768)]
[New Thread 0x7fffe6d31700 (LWP 14769)]
[New Thread 0x7fffe5e7e700 (LWP 14770)]

(easytag:14763): GLib-GIO-CRITICAL **: g_input_stream_read_all:
assertion 'buffer != NULL' failed **
ERROR:src/file.c:1433:ET_Save_File_Tag_To_HD: assertion failed: (error
== NULL || *error != NULL)

Program received signal SIGABRT, Aborted.
0x00007ffff4368458 in raise () from /lib/x86_64-linux-gnu/libc.so.6

Best regards
malenki