Tremolos collide with accidentals on tremolo'd notes

Latest master. See attached score and image below.

Reproduce:

1. Create a score from the Treble Clef template, or use any score that has as many bars as horizontally possible in one system.
2. Add a tremolo between two notes
3. Select one, and shift it up a semitone

Result:
The tremolo symbol collides with the note accidental.

Expected result:
Space is allocated such that the tremolo symbol doesn't collide.

This layout bug is also present in 2.3.2.