Initial proto for language detection.

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 4f9da7374f9c8cc583eda08b01441f3baf144ffb..1c43b1f485b5e2079269c893a40b1ff97de135fe 100644
--- a/components/sync/protocol/proto_visitors.h
+++ b/components/sync/protocol/proto_visitors.h
@@ -540,6 +540,16 @@ VISIT_PROTO_FIELDS(const sync_pb::KeystoreEncryptionFlags& proto) {
   VISIT(enabled);
 }
 
+VISIT_PROTO_FIELDS(const sync_pb::LanguageDetection::Language& proto) {
+  VISIT(language_code);
+  VISIT(proportion);
+}
+
+VISIT_PROTO_FIELDS(const sync_pb::LanguageDetection& proto) {
+  VISIT_REP(detected_languages);
+  VISIT(adopted_language);
+}
+
 VISIT_PROTO_FIELDS(const sync_pb::LinkedAppIconInfo& proto) {
   VISIT(url);
   VISIT(size);
@@ -861,6 +871,7 @@ VISIT_PROTO_FIELDS(const sync_pb::UserEventSpecifics& proto) {
   VISIT(navigation_id);
   VISIT(session_id);
   VISIT(field_trial_event);
+  VISIT(translate_language_detection);
 }
 
 VISIT_PROTO_FIELDS(const sync_pb::WalletMaskedCreditCard& proto) {