MP4 reader: improve test for identical edit list entries

In #2306 a file was provided with an edit list consisting of two
identical entries that span the whole duration of the file as given by
the file headers. The difference to earlier provided files is that the
edits don't start at 0 but slightly later. Therefore a check for
"starting at 0" seems counterproductive.

Fixes #2306.

NEWS.md

@@ -6,6 +6,9 @@
   extraction as other tools such as MP4Box cannot handle them
   correctly. Implements #2293.
 * mkvmerge, mkvextract: AVC/h.264: empty NALUs will now be removed.
+* mkvmerge: MP4 reader: improved the detection of edit lists consisting of two
+  identical entries, each spanning the file's duration as given in the movie
+  header atom. The second entry is ignored in such cases. See #2306.
 
 ## Bug fixes
 

src/input/r_qtmp4.cpp

@@ -2451,10 +2451,9 @@ qtmp4_demuxer_c::apply_edit_list() {
       edit.segment_duration = 0;
       mxdebug_if(m_debug_editlists, boost::format("  %1%: single edit with positive media_time; track start offset %2%; change to non-edit to copy the rest\n") % info % format_timestamp(timeline_cts));
 
-    } else if (   (num_edits       == 2)
-               && (entry_index     == 2)
-               && (edit            == editlist_table.front())
-               && (edit.media_time == 0)
+    } else if (   (num_edits   == 2)
+               && (entry_index == 2)
+               && (edit        == editlist_table.front())
                && m_reader.m_duration
                && ((timeline_cts - static_cast<int64_t>(*m_reader.m_duration)) >= timestamp_c::s(-60).to_ns())) {
       mxdebug_if(m_debug_editlists,