Manifest for Android Wear O Preview 4

Change-Id: Ie284cc57b94e6c9e537774b5b576298e7ec3a66c
diff --git a/default.xml b/default.xml
index 36840de..7643bc2 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-wear-o-preview-3"
+  <default revision="refs/tags/android-wear-o-preview-4"
            remote="aosp"
            sync-j="4" />