Manifest for Android 8.1.0 Release 40 (OPM4.171019.021.R1)

Change-Id: Ib5b8c3aeb3167411202a125eb4cd5c10b87a2e71
diff --git a/default.xml b/default.xml
index 1a96670..a50ca7d 100644
--- a/default.xml
+++ b/default.xml
@@ -4,7 +4,7 @@
   <remote  name="aosp"
            fetch=".."
            review="https://android-review.googlesource.com/" />
-  <default revision="refs/tags/android-8.1.0_r33"
+  <default revision="refs/tags/android-8.1.0_r40"
            remote="aosp"
            sync-j="4" />