Use full import paths for test protos.
diff --git a/proto/equal_test.go b/proto/equal_test.go
index cc25833..b322f65 100644
--- a/proto/equal_test.go
+++ b/proto/equal_test.go
@@ -34,8 +34,8 @@
 import (
 	"testing"
 
-	pb "./testdata"
 	. "github.com/golang/protobuf/proto"
+	pb "github.com/golang/protobuf/proto/testdata"
 )
 
 // Four identical base messages.