Move comment to license_note

Comments not preserved during refresh.

Test: m nothing
Change-Id: Ib3b4508b26577d9a6032d2483111114c1e440cd0
diff --git a/METADATA b/METADATA
index a0099a3..de81673 100644
--- a/METADATA
+++ b/METADATA
@@ -1,9 +1,9 @@
 third_party {
-  # would be NOTICE save for GPL in:
-  #   common/py3-stdlib/urllib/robotparser.py
-  #   common/bison/... see:
-  #     common/bison/README.md
-  #     common/bison/NOTICE
-  #     plus copyright headers
+  license_note: "would be NOTICE save for GPL in:\n"
+  "   common/py3-stdlib/urllib/robotparser.py\n"
+  "   common/bison/... see:\n"
+  "     common/bison/README.md\n"
+  "     common/bison/NOTICE\n"
+  "     plus copyright headers"
   license_type: RESTRICTED
 }