widening: remove always-true condition in widening code

The function is now specifically about widening, so we don't need to
check if we're widening.

Differential Revision: https://phab.mercurial-scm.org/D7094

hgext/narrow/narrowbundle2.py

@@ -134,7 +134,6 b' def generate_ellipses_bundle2_for_wideni'
 
     heads = set(heads or repo.heads())
     common = set(common or [nullid])
-    if known and (oldinclude != newinclude or oldexclude != newexclude):
         # Steps:
         # 1. Send kill for "$known & ::common"
         #