UserEvent proto exploration for 0-Suggest use case.

components/sync/protocol/proto_visitors.h

Index: components/sync/protocol/proto_visitors.h
diff --git a/components/sync/protocol/proto_visitors.h b/components/sync/protocol/proto_visitors.h
index 31b343b39645d0fd515994eb2d5198540686d3d6..104361980b62909b30364a6f4110d347de20fd5d 100644
--- a/components/sync/protocol/proto_visitors.h
+++ b/components/sync/protocol/proto_visitors.h
@@ -851,6 +851,8 @@ VISIT_PROTO_FIELDS(const sync_pb::UserEventSpecifics& proto) {
   VISIT(event_time_usec);
   VISIT(navigation_id);
   VISIT(session_id);
+  VISIT(zero_suggest_request);
+  VISIT(zero_suggest_selected);
 }
 
 VISIT_PROTO_FIELDS(const sync_pb::WalletMaskedCreditCard& proto) {
@@ -901,6 +903,15 @@ VISIT_PROTO_FIELDS(const sync_pb::WifiCredentialSpecifics& proto) {
   VISIT_BYTES(passphrase);
 }
 
+VISIT_PROTO_FIELDS(const sync_pb::ZeroSuggestRequest proto) {
+  VISIT(cusco_request_id);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::ZeroSuggestSelected proto) {
+  VISIT(request_event_id);
+  VISIT(index_selected);
+}
+
 }  // namespace syncer
 
 #undef VISIT_