The go_seq_to_refnum function handles its argument object as a Java
object if it doesn't implement Seq.Proxy. Java classes implemented in
Go does not implement Seq.Proxy, but when passing "this" references to
Go, instances must be treated as a Go object.
Use go_seq_to_refnum_go everywhere "this" is passed to Go, which fixes
field accessors and simplifies the method call case.
Change-Id: I3d01c63d7b2081e6344ece431f5e5021a9dd7662
Reviewed-on: https://go-review.googlesource.com/31171
Reviewed-by: David Crawshaw <crawshaw@golang.org>
63993740dd