Create syncable metadata table for Wallet credit cards and addresses.

sync/protocol/autofill_specifics.proto

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 //
 // Sync protocol datatype extension for autofill.
 
 // Update proto_value_conversions{.h,.cc,_unittest.cc} if you change
 // any fields in this file.
 
 syntax = "proto2";
@@ skipping 98 matching lines @@
   // Month number 1-12.
   optional int32 exp_month = 6;
 
   // Four-digit year (e.g. 2017).
   optional int32 exp_year = 7;
 }
 
 // Different than an AutofillProfile because this represents some known address
 // on the server that is pulled down rather than synced between Chromes.
 message WalletPostalAddress {
-  // Server-generated unique ID string. This is opaque to the client.
+  // DEPRECATED
   optional string id = 1;
 
   optional string recipient_name = 12;
   optional string company_name = 2;
 
   // This is the street address, of which there may be multiple lines. This
   // corresponds to "address_home_line[1|2] in the AutofillProfileSpecifics
   // message above. In some locales there may be more than two lines.
   repeated string street_address = 3;
 
@@ skipping 34 matching lines @@
 
   optional WalletInfoType type = 1;
 
   // This field exists if and only if the "type" field equals to
   // MASKED_CREDIT_CARD.
   optional WalletMaskedCreditCard masked_card = 2;
 
   // This field exists if and only if the "type" field equals to ADDRESS.
   optional WalletPostalAddress address = 3;
 }