bogus test: planning to allow forward declarations

of structs/interfaces in other files in the package.

R=r
DELTA=12  (0 added, 12 deleted, 0 changed)
OCL=30865
CL=30868

test/export.go

-// Copyright 2009 The Go Authors.  All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// errchk $G $D/$F.go
-
-package main
-
-type A struct		// ERROR "incomplete"
-type B interface	// ERROR "incomplete"
-
-type C struct
-type D interface
-
-type C struct { }
-type D interface { }