Test suite notices using dependencies.

Switch from combine-notice-files to html-notice-rule and
text-notice-rule.

Bug: 151177513
Bug: 213388645
Bug: 210912771

Test: m cts reportmissinglicenses
Change-Id: I59d78553f15f0fd6be87228c933693b63e2ebf04
diff --git a/core/clear_vars.mk b/core/clear_vars.mk
index 57f9ef8..b5b371c 100644
--- a/core/clear_vars.mk
+++ b/core/clear_vars.mk
@@ -510,6 +510,8 @@
 full_android_manifest :=
 non_system_module :=
 
+module_license_metadata :=
+
 # Trim MAKEFILE_LIST so that $(call my-dir) doesn't need to
 # iterate over thousands of entries every time.
 # Leave the current makefile to make sure we don't break anything