Search Highlighting off by 1 error

[tomlm]

Summary

When using AvaloniaEdit in Consolonia, it highlights an off by one error which is amplified because in consolonia 1px = fontsize=1.

Behavior

• Search hit highlighting highlights the correct region when the scroll view as at the top of the viewport
• Search hit highlighting highlights the line below the correct line when the scroll view has scrolled at all.

(See image, public is highlighted correctly at top of file, but not when scrolled)

Repo

1. enlist in https://github.com/consolonia/Consolonia.AvaloniaEdit
2. Run Consolonia.Editor sample project
3. Search for "public" and cycle through Next/Next/Next until it wraps back to the top.

Expected

Behavior is the same when scrolling.

NOTE: It may be related to #526 ?