cmd/gc: fix incomplete export data when inlining with local variables.

When local declarations needed unexported types, these could
be missing in the export data.

Fixes build with -gcflags -lll, except for exp/gotype.

R=golang-dev, rsc, lvd
CC=golang-dev
https://golang.org/cl/6813067
diff --git a/test/fixedbugs/bug467.go b/test/fixedbugs/bug467.go
new file mode 100644
index 0000000..d73adba
--- /dev/null
+++ b/test/fixedbugs/bug467.go
@@ -0,0 +1,10 @@
+// compiledir
+
+// Copyright 2012 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.
+
+// Exported data for inlining could forget types of
+// local variables declared in inlinable bodies.
+
+package ignored