Add OWNERS file for libstats/

Test: N/A
Change-Id: Ic16b0e1330ff46bfea9524eacf109c4ded430c67
diff --git a/libstats/OWNERS b/libstats/OWNERS
new file mode 100644
index 0000000..ed06fbc
--- /dev/null
+++ b/libstats/OWNERS
@@ -0,0 +1,4 @@
+bookatz@google.com
+joeo@google.com
+yaochen@google.com
+yanglu@google.com