Fake selection marker for collapsed and non-collapsed selections for link UI should be converted separately

[niegowski]

Suggested merge commit message (convention)

Other (link): Fake selection marker for collapsed and non-collapsed selections for link UI should be converted separately. Closes #8092.

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Additional information

The problem with downcasting link-ui marker was that two separate converters were defined for the same marker:

• markerToHighlight - for the non collapsed selection.
• markerToElement - for the collapsed selection (but this converter also works correctly for non collapsed selection - it inserts elements at both ends of the marker range).

[scofalik]

I reviewed this solution and I don't really like having two markers for the same thing. This is why I asked @niegowski to check alternative solution, which still has only one marker but the marker range is modified. It is similar to Radek's solution but it should be easier (less lines of code) as I proposed using position.getLastMatchingPosition() to move starting position to a proper place.

[niegowski]

I reviewed this solution and I don't really like having two markers for the same thing. This is why I asked @niegowski to check alternative solution, which still has only one marker but the marker range is modified. It is similar to Radek's solution but it should be easier (less lines of code) as I proposed using position.getLastMatchingPosition() to move starting position to a proper place.

This solution is much simpler 🙂 I just pushed the fix.