Fix documentation for android_app_import

Test: N/A
Fix: 226586426
Change-Id: I588a249a85d152f37f5d1bd7157cfab120185648
diff --git a/java/app_import.go b/java/app_import.go
index a1c4d58..b017eca 100644
--- a/java/app_import.go
+++ b/java/app_import.go
@@ -466,7 +466,7 @@
 //                 apk: "prebuilts/example_xhdpi.apk",
 //             },
 //         },
-//         certificate: "PRESIGNED",
+//         presigned: true,
 //     }
 func AndroidAppImportFactory() android.Module {
 	module := &AndroidAppImport{}