[Sync] Filter out types that can't be synced at configure time.

ios/chrome/browser/sync/ios_chrome_sync_client.mm

 // 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 "ios/chrome/browser/sync/ios_chrome_sync_client.h"
 
 #include <utility>
 
 #include "base/bind.h"
 #include "base/command_line.h"
@@ skipping 184 matching lines @@
   return ios::FaviconServiceFactory::GetForBrowserState(
       browser_state_, ServiceAccessType::EXPLICIT_ACCESS);
 }
 
 history::HistoryService* IOSChromeSyncClient::GetHistoryService() {
   DCHECK_CURRENTLY_ON(web::WebThread::UI);
   return ios::HistoryServiceFactory::GetForBrowserState(
       browser_state_, ServiceAccessType::EXPLICIT_ACCESS);
 }
 
+bool IOSChromeSyncClient::HasPasswordStore() {
+  DCHECK_CURRENTLY_ON(web::WebThread::UI);
+  return password_store_ != nullptr;
+}
+
 autofill::PersonalDataManager* IOSChromeSyncClient::GetPersonalDataManager() {
   DCHECK_CURRENTLY_ON(web::WebThread::UI);
   return autofill::PersonalDataManagerFactory::GetForBrowserState(
       browser_state_);
 }
 
 base::Closure IOSChromeSyncClient::GetPasswordStateChangedCallback() {
   return base::Bind(
       &IOSChromePasswordStoreFactory::OnPasswordsSyncedStatePotentiallyChanged,
       base::Unretained(browser_state_));
@@ skipping 197 matching lines @@
         IOSChromeProfileSyncServiceFactory::GetForBrowserState(browser_state);
     if (profile_sync_service != nullptr) {
       const syncer::DeviceInfoTracker* tracker =
           profile_sync_service->GetDeviceInfoTracker();
       if (tracker != nullptr) {
         trackers->push_back(tracker);
       }
     }
   }
 }