Manifest for Android 7.1.2 Release 12 (N2G47W)

Change-Id: I8012e27823796d184ef5f3fd5680b21e045ffa9f
diff --git a/default.xml b/default.xml
index e559477..6c9c89d 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-7.1.2_r11"
+  <default revision="refs/tags/android-7.1.2_r12"
            remote="aosp"
            sync-j="4" />