Lineage properties support module references.

They should have had `android:"path"` tags attached so that users can
point them to filegroup modules.

Test: app_test.go & app_import_test.go
Bug: 182175153
Change-Id: I5580408488ffe5fc12c869cbfb7a468713dcbc96
diff --git a/java/app_import.go b/java/app_import.go
index d38f63e..d4da64d 100644
--- a/java/app_import.go
+++ b/java/app_import.go
@@ -74,8 +74,8 @@
 	// be set for presigned modules.
 	Presigned *bool
 
-	// Name of the signing certificate lineage file.
-	Lineage *string
+	// Name of the signing certificate lineage file or filegroup module.
+	Lineage *string `android:"path"`
 
 	// Sign with the default system dev certificate. Must be used judiciously. Most imported apps
 	// need to either specify a specific certificate or be presigned.