MrJul/ReSharper.EnhancedTooltip — pull request #1 by citizenmatt (2013-12-11 11:01:07+00:00)
Title: Added grey text for no parameters

Shame it's hardcoded to grey, but there's no other highlight id to pinch, and it's a bit overkill to create another. Looks find on Dark, Light and Blue themes.