Update protobuf owners file

Change-Id: I6cbdb09d464f894dd3422afd4b8348965f6f96a7
Reviewed-on: https://fuchsia-review.googlesource.com/c/third_party/protobuf/+/641866
Reviewed-by: Francois Rousseau <frousseau@google.com>

OWNERS

diff --git a/OWNERS b/OWNERS
index 8f39fac..2930997 100644
--- a/OWNERS
+++ b/OWNERS
@@ -1,7 +1,8 @@
+anhwang@google.com
 azani@google.com
 camrdale@google.com
+frousseau@google.com
 jaredweinstein@google.com
-ninai@google.com
 pesk@google.com
 stevefung@google.com
 zmbush@google.com