Fix setup trigger issue under sharing and transforms.
There was a subtle bug in the case of using a shared module that defined
a setup() method that was called first at one location under a transform
(like remat or jit) and at another location without the transform.
In the latter case the "outside" instance of the submodule had had a
"shallow" _try_setup call pre-transform and was then marked as having
had setup called, but the setup method had not in fact been called.
This requires a one-line logic fix in _try_setup().
