Can't upgrade PostGIS with extension

[robe]

This I suspect is just an extension issue and I have to put in extra logic for this. I'll double check but I did my usual micro-micro upgrade

Upgrading from 2.1.0 SVN r11142 to r11306

with

ALTER EXTENSION postgis UPDATE TO "2.1.0SVNnext";

and got this

ERROR:  cannot drop function geometry_gist_sel_2d(internal,oid,internal,integer) because other objects depend on it