Remove code that cannot compile on SE 17

We are currently testing SE 17 by compiling with SE 8 and then testing with SE 17, using a profile that prevents any re-compilation. That differs from how we've handled SE 11 for many years, where we build and test in one go with the same SE.

We're at a stage now where we shouldn't have code that requires APIs that have been removed in SE 17, so this task is to get rid of any remaining cruft.