i.e lots now able to be detected after...

commit b44cbb26
Author: Noel Grandin <noel@peralex.com>
Date:   Tue Jan 20 12:38:10 2015 +0200

    new loplugin: change virtual methods to non-virtual

    Where we can prove that the virtual method is never overriden.

    In the case of pure-virtual methods, we remove the method entirely.
    Sometimes this leads to entire methods and fields being
    eliminated.

Change-Id: I605e2fa56f7186c3d3a764f3cd30f5cf7f881f9d