Barlines on a 1 line percussion staff

When a score contains multiple 1 line percussion staves, the opening barline extends above the top staff, but it does not extend below the lowest staff.

According to pages 271 and 534 of Elaine Gould's Behind Bars, the opening barline should extend beyond both staves equally, just like all the other barlines do (though not necessarily by the same amount as all the other barlines).

Stave brackets on 1 lines staves needs to be made longer (see #290409: Stave brackets disappear on a 1 line percussion staff). When this is done, it will define the limit of the barline extensions:

• The opening barline on a 1 line staff should have small extensions that are fully enclosed within the straight part of the bracket.
• The other barlines can be longer, but they should still fit comfortably within the tips of the bracket's curve.
• When no bracket is present, the opening barline should be the same length as the other barlines.

Here is a mock-up of how it should look when a bracket is present:

For ease of implementation, it might be best to make all barlines the same length all the time, like this:

The barlines could be a bit longer than that, but then the bracket would need to be made longer too of course. If the bracket is made too long then it will end up longer for a 1 line staff than it currently is for a 2 line staff.