exp/types: properly read dotted identifiers

Fixes #3682.

R=rsc
CC=golang-dev
https://golang.org/cl/6256067

src/pkg/exp/types/gcimporter.go

@@ -182,7 +182,7 @@ func (p *gcParser) init(filename, id string, src io.Reader, imports map[string]*
 func (p *gcParser) next() {
 	p.tok = p.scanner.Scan()
 	switch p.tok {
-	case scanner.Ident, scanner.Int, scanner.String:
+	case scanner.Ident, scanner.Int, scanner.String, '·':
 		p.lit = p.scanner.TokenText()
 	default:
 		p.lit = ""

src/pkg/exp/types/gcimporter_test.go

@@ -92,13 +92,6 @@ func testDir(t *testing.T, dir string, endTime time.Time) (nimports int) {
 }
 
 func TestGcImport(t *testing.T) {
-	// Dies trying to read crypto/md5, which contains
-	//	const init1 = 0x...
-	// The importer believes init1 should be a function for some reason.
-	// golang.org/issue/3682.
-	t.Logf("broken; skipping")
-	return
-
 	// On cross-compile builds, the path will not exist.
 	// Need to use GOHOSTOS, which is not available.
 	if _, err := os.Stat(gcPath); err != nil {

src/pkg/exp/types/testdata/exports.go

@@ -11,6 +11,11 @@ import (
 	"go/ast"
 )
 
+// Issue 3682: Correctly read dotted identifiers from export data.
+const init1 = 0
+
+func init() {}
+
 const (
 	C0 int = 0
 	C1     = 3.14159265