zero-length-notes added to normal-notes does only play the bar with the normal-note

[musikBear]

Zero-length notes added to normal notes only play when in the bar with the normal note.

Bug Summary

When deciding where to loop, the piano roll does not account for zero-length notes when there are non-zero-length notes present (see gif below). Related: #5339

Steps to reproduce

• Open a block in piano-roll. Insert one normal note.
• Copy a several bar long pattern made in the B&B-editor. Insert it in newly made block.
• Play.

Expected behavior

• All notes should play normally both in the piano roll and the song editor.

Actual behavior

• The piano roll will not continue playing to the additional bar.

Screenshot

LMMS version used

1.2.1 on Windows 10

Demo file:
zero-length-notesApart121.zip

SecondFlight: move info to bug description, clarify, and add screen recording