Add default active developers into OWNERS

Bug: 33166666
Test: gerrit uploader
Change-Id: Ia47fbf6ce98f78d7eacf9a4a02495666ca107def
diff --git a/OWNERS b/OWNERS
new file mode 100644
index 0000000..4d9907d
--- /dev/null
+++ b/OWNERS
@@ -0,0 +1 @@
+yim@google.com