The wrap highlighter was pulling all lines until the cursor, regardless
of whether the cursor was going to be made visible, this could lead to
a display buffer containing much more lines than the actual viewport
which eventually could lead to menu being anchored out of view that
was leading to past-the-end buffer accesses.
Fix the wrap higlighter not to pull lines up to the cursor when it
is not tasked with making the cursor visible, and always trim the
eventual extra lines after highlighting.
Fixes#5118
