Generate simpler code for zero-param blocks.
Generate simpler code for zero-param blocks.

They no longer need an array constructing and passing, which is then
checked through the binder. Instead, this happens from the outside.
Not quite specializing it through indy yet.

cygx/nqp,cygx/nqp,cygx/nqp,cygx/nqp,cygx/nqp,cygx/nqp,cygx/nqp,cygx/nqp