hide the nanos even harder

Bug: 26925668
Change-Id: Ic56460926bd62ac41e64f4d37f52d962976ca644
diff --git a/proto/jarjar-rules.txt b/proto/jarjar-rules.txt
index 0c77c2a..50220b4 100644
--- a/proto/jarjar-rules.txt
+++ b/proto/jarjar-rules.txt
@@ -1 +1,2 @@
-rule com.google.** com.android.@1
+rule com.google.protobuf.nano.** com.android.framework.protobuf.nano.@1
+