Add default active developers into OWNERS

Bug: 33166666
Test: gerrit uploader
Change-Id: I9b3bb9dd620bdef18750568ed79330f3c9b1c8af
diff --git a/OWNERS b/OWNERS
new file mode 100644
index 0000000..4d9907d
--- /dev/null
+++ b/OWNERS
@@ -0,0 +1 @@
+yim@google.com