test: match gccgo error messages

Added a return to bug357.go to avoid an error which gccgo
reports but 6g does not.

bug353.go:16:14: error: reference to undefined identifer ‘io.ReadWriterCloser’

bug357.go:18:2: error: value computed is not used

bug358.go:14:11: error: imported and not used: ioutil
bug358.go:19:9: error: invalid use of type

bug359.go:25:14: error: redefinition of ‘a’
bug359.go:25:6: note: previous definition of ‘a’ was here
bug359.go:19:6: error: incompatible type in initialization (implicit assignment of ‘list.List’ hidden field ‘front’)

bug362.go:13:6: error: iota is only defined in const declarations
bug362.go:14:6: error: iota is only defined in const declarations
bug362.go:15:6: error: iota is only defined in const declarations

bug363.go:13:12: error: shift of non-integer operand
bug363.go:16:12: error: shift of non-integer operand

bug365.go:15:8: error: expected package

R=golang-dev, gri
CC=golang-dev
https://golang.org/cl/5078046
diff --git a/test/fixedbugs/bug358.go b/test/fixedbugs/bug358.go
index cc622c0..f43709b 100644
--- a/test/fixedbugs/bug358.go
+++ b/test/fixedbugs/bug358.go
@@ -11,12 +11,12 @@
 
 import (
 	"http"
-	"io/ioutil"
+	"io/ioutil"	// GCCGO_ERROR "imported and not used"
 	"os"
 )
 
 func makeHandler(fn func(http.ResponseWriter, *http.Request, string)) http.HandlerFunc {
-	return func(w http.ResponseWriter, r *http.Request)  // ERROR "syntax error"
+	return func(w http.ResponseWriter, r *http.Request)  // ERROR "syntax error|invalid use of type"
 }
 
 type Page struct {