Keep Notice property from erasing license texts.

Remove "default to file in directory". Use explicit applicable license.

Bug: 192434786

Test: m droid dist

Change-Id: Id3d845b2073f151a8c0bad874e7ab005771bdfcb
diff --git a/android/androidmk.go b/android/androidmk.go
index 832c7df..d6fe06d 100644
--- a/android/androidmk.go
+++ b/android/androidmk.go
@@ -605,7 +605,7 @@
 	}
 
 	if len(base.noticeFiles) > 0 {
-		a.SetString("LOCAL_NOTICE_FILE", strings.Join(base.noticeFiles.Strings(), " "))
+		a.AddStrings("LOCAL_NOTICE_FILE", strings.Join(base.noticeFiles.Strings(), " "))
 	}
 
 	if host {