Reference Search Annotation does not disappear after removing Search Result

[tsmaeder]

Bug Description:

When we search for references and open an editor containing a reference, the range of the reference is shown in the editor with a different background (orange in my Theme). When we delete results from the reference search (there is an "x" when hovering over the results), the corresponding colored background is not removed. When I reopen the editor, the background coloring is gone.

Steps to Reproduce:

see description.

Additional Information

• Operating System: Windows
• Theia Version: 1.40.0 master