Manifest for Android 7.0.0 Release 28 (NBD91Y)

Change-Id: Ibd1cd52c23ee8adff45d25cc73bf3f244db57a3d
diff --git a/default.xml b/default.xml
index 02891b5..f0d31eb 100644
--- a/default.xml
+++ b/default.xml
@@ -3,7 +3,7 @@
 
   <remote  name="aosp"
            fetch=".." />
-  <default revision="refs/tags/android-7.0.0_r27"
+  <default revision="refs/tags/android-7.0.0_r28"
            remote="aosp"
            sync-j="4" />