In the previous line number CL the NewValue\d? functions took
a line number argument but neglected to set the Line field on
the value struct. Fix that.

Change-Id: I53c79ff93703f66f5f0266178c94803719ae2074
Reviewed-on: https://go-review.googlesource.com/11054Reviewed-by: Keith Randall <khr@golang.org>