Add license type: Apache2+MIT+BSD = NOTICE licenses

Bug: 68860345
Bug: 69058154
Bug: 151953481

Test: no code changes

Exempt-From-Owner-Approval: janitorial work

Change-Id: Iafdb5be4d3f72d79d55e1481f4234c3886bf6138
diff --git a/METADATA b/METADATA
index 9556624..cfd0a77 100644
--- a/METADATA
+++ b/METADATA
@@ -12,5 +12,6 @@
     value: "https://files.pythonhosted.org/packages/a6/5b/f399fcffb9128d642387133dc3aa9bb81f127b949cd4d9f63e5602ad1d71/setuptools-39.1.0.zip"
   }
   version: "v39.1.0"
+  license_type: NOTICE
   last_upgrade_date { year: 2018 month: 5 day: 23 }
 }