test: add test case for issue 8154

Updates #8154

Change-Id: Ie9c731a91b008277e51c723eef6871bb0919fa4c
Reviewed-on: https://go-review.googlesource.com/10831Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Russ Cox <rsc@golang.org>

test/fixedbugs/issue8154.go

+// compile
+
+// Copyright 2015 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.
+
+// Issue 8154: cmd/5g: ICE in walkexpr walk.c
+
+package main
+
+func main() {
+	c := make(chan int)
+	_ = [1][]func(){[]func(){func() { <-c }}}
+}