[Bf-committers] edge slide bug + cause

[Antony Riakiotakis]

One way to do it is make sure that we pass BMO_op_initf(bm, &findop,
"finddoubles verts=%hv keepverts=%fv", VERT_KEEP); instead of
BMO_op_initf(bm, &findop, "finddoubles verts=%av keepverts=%fv",
VERT_KEEP); in bmesh_automerge_exec. Do we usually automerge with
hidden vertices?

Another way is to cleanup the temporary faces in
special_aftertrans_update just before the EDBM_automerge call (it's a
-special- update after all ;) ). It will make the code a bit less
generic because we have to check if the type of the transform is edge
slide but it will work.