Change uses of base::JoinString to pass StringPieces where possible.

components/autofill/core/browser/webdata/autofill_wallet_syncable_service.cc

 // Copyright 2015 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.
 
 #include "components/autofill/core/browser/webdata/autofill_wallet_syncable_service.h"
 
 #include <stddef.h>
 
 #include <set>
 #include <utility>
 
 #include "base/logging.h"
+#include "base/strings/string_piece.h"
 #include "base/strings/string_util.h"
 #include "base/strings/utf_string_conversions.h"
 #include "components/autofill/core/browser/webdata/autofill_table.h"
 #include "components/autofill/core/browser/webdata/autofill_webdata_backend.h"
 #include "components/autofill/core/browser/webdata/autofill_webdata_service.h"
 #include "components/sync/model/sync_error_factory.h"
 #include "components/sync/protocol/sync.pb.h"
 
 namespace autofill {
 
@@ skipping 56 matching lines @@
   result.SetExpirationYear(card.exp_year());
   result.set_billing_address_id(card.billing_address_id());
   return result;
 }
 
 AutofillProfile ProfileFromSpecifics(
     const sync_pb::WalletPostalAddress& address) {
   AutofillProfile profile(AutofillProfile::SERVER_PROFILE, std::string());
 
   // AutofillProfile stores multi-line addresses with newline separators.
-  std::vector<std::string> street_address(address.street_address().begin(),
-                                          address.street_address().end());
+  std::vector<base::StringPiece> street_address(
+      address.street_address().begin(), address.street_address().end());
   profile.SetRawInfo(ADDRESS_HOME_STREET_ADDRESS,
                      base::UTF8ToUTF16(base::JoinString(street_address, "\n")));
 
   profile.SetRawInfo(COMPANY_NAME, base::UTF8ToUTF16(address.company_name()));
   profile.SetRawInfo(ADDRESS_HOME_STATE,
                      base::UTF8ToUTF16(address.address_1()));
   profile.SetRawInfo(ADDRESS_HOME_CITY,
                      base::UTF8ToUTF16(address.address_2()));
   profile.SetRawInfo(ADDRESS_HOME_DEPENDENT_LOCALITY,
                      base::UTF8ToUTF16(address.address_3()));
@@ skipping 251 matching lines @@
   merge_result.set_num_items_after_association(
       static_cast<int>(wallet_cards.size() + wallet_addresses.size()));
 
   if (webdata_backend_ && (changed_cards || changed_addresses))
     webdata_backend_->NotifyOfMultipleAutofillChanges();
 
   return merge_result;
 }
 
 }  // namespace autofil