DO NOT MERGE ANYWHERE Create manifest for emu-gn-dev

Change-Id: I8ebeefa01a41e364cbde9aebbce573a108a9f027
BUG: 78900680
diff --git a/default.xml b/default.xml
index bfdd281..6d94a13 100644
--- a/default.xml
+++ b/default.xml
@@ -4,7 +4,7 @@
   <remote  name="aosp"
            fetch=".."
            review="https://android-review.googlesource.com/" />
-  <default revision="emu-master-dev"
+  <default revision="emu-gn-dev"
            remote="aosp"
            sync-j="4" />