Update Moblab's OWNERS

BUG=b:218521862
TEST=not applicable, just OWNERS change

Change-Id: I87cdba8a4864c3844eee88e9c71f26943c2065d7
diff --git a/OWNERS b/OWNERS
index cecfdf7..4e2eeb3 100644
--- a/OWNERS
+++ b/OWNERS
@@ -1,7 +1,7 @@
 set noparent
-ntang@chromium.org
-haddowk@chromium.org
 stephenlin@chromium.org
 wangmichael@chromium.org
 zhihuixie@chromium.org
 ivanbrovkovich@chromium.org
+varunth@google.com
+mmatyjek@google.com