components: Add out-of-line copy ctors for complex classes.

components/signin/core/browser/account_info.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/signin/core/browser/account_info.h"
 
 namespace {
 
 bool UpdateField(std::string* field, const std::string& new_value) {
   bool should_update = field->empty() && !new_value.empty();
@@ skipping 13 matching lines @@
 AccountInfo::AccountInfo()
     : account_id(),
       gaia(),
       email(),
       full_name(),
       given_name(),
       hosted_domain(),
       locale(),
       picture_url(),
       is_child_account(false) {}
+AccountInfo::AccountInfo(const AccountInfo& other) = default;
 AccountInfo::~AccountInfo() {}
 
 bool AccountInfo::IsValid() const {
   return !account_id.empty() && !email.empty() && !gaia.empty() &&
          !hosted_domain.empty() && !full_name.empty() && !given_name.empty() &&
          !locale.empty() && !picture_url.empty();
 }
 
 bool AccountInfo::UpdateWith(const AccountInfo& other) {
   if (account_id != other.account_id) {
     // Only updates with a compatible AccountInfo.
     return false;
   }
 
   bool modified = UpdateField(&gaia, other.gaia);
   modified |= UpdateField(&email, other.email);
   modified |= UpdateField(&full_name, other.full_name);
   modified |= UpdateField(&given_name, other.given_name);
   modified |= UpdateField(&hosted_domain, other.hosted_domain);
   modified |= UpdateField(&locale, other.locale);
   modified |= UpdateField(&picture_url, other.picture_url);
   modified |= UpdateField(&is_child_account, other.is_child_account);
 
   return modified;
 }