Add missing metalava options to framework-module-defaults

Bug: 155164730
Test: m droid
Change-Id: I7a852149e3e12c3cb9083b2d0ca483cc55f6348f
diff --git a/apex/Android.bp b/apex/Android.bp
index e8afa1d..f511af5 100644
--- a/apex/Android.bp
+++ b/apex/Android.bp
@@ -92,6 +92,9 @@
         sdk_version: "module_current",
     },
 
+    // Configure framework module specific metalava options.
+    droiddoc_options: [mainline_stubs_args],
+
     // The stub libraries must be visible to frameworks/base so they can be combined
     // into API specific libraries.
     stubs_library_visibility: [