It is not possible to extend highlight past the newline (till the end of the visual line) in the editor. If the highlight defines a background, then the editor changes background just up to the newline, which looks ugly.
This was fixed in trunk as http://hg.netbeans.org/jet-main/rev/35c506a540e7 and could be backported to NB-8.2
Backported as 606211bc9192
I think that the patch is ok.
It could possibly be composed to only query token.getProperty("highlight.block") if the token really contains the newline but most of the tokens are default tokens anyway that do not carry actual properties so the performance gain would be minimal so let's have it as it is now.