Small attribute annotations cause indent guidelines broken

[laicasaane]

I'm using Indent Guides in conjunction with Codist and recently I notice that when attribute annotations are smaller than the default size, indent guidelines will jump around when the vertical scrollbar of a document is at some specific position.

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Forward from wmjordan/Codist#345.

Codist's author said he can't do anything about this so I present it here to seek your opinion on this matter.

I'm currently on VS 17.12.4.

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This is a capture to demonstrate the issue:

403678902-3a330e29-f600-40da-a08c-d68242a00fb6.mp4

[zooba]

Yeah, this probably needs a change to this line to be able to cope with other adornment layers or things that interfere with the text.

I don't know off the top of my head what that change would be, and I'm unlikely to get a chance to figure it out, but if someone does then feel free to post a PR and if it seems reasonable I can merge it.