Manifest for Android 7.1.1 Release 31 (N4F26U)

Change-Id: I3aed420575402c4382f49e0275211555ab547732
diff --git a/default.xml b/default.xml
index 88867b9..f2f037d 100644
--- a/default.xml
+++ b/default.xml
@@ -3,7 +3,7 @@
 
   <remote  name="aosp"
            fetch=".." />
-  <default revision="refs/tags/android-7.1.1_r24"
+  <default revision="refs/tags/android-7.1.1_r31"
            remote="aosp"
            sync-j="4" />