[sync] Reland of "TwoClientBookmarksSyncTest.Sanity" is flaky

components/sync/driver/glue/sync_backend_host_impl.cc

 // Copyright 2013 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/sync/driver/glue/sync_backend_host_impl.h"
 
 #include <utility>
 
 #include "base/bind.h"
 #include "base/command_line.h"
@@ skipping 91 matching lines @@
 
   base::CommandLine* cl = base::CommandLine::ForCurrentProcess();
   if (cl->HasSwitch(switches::kSyncShortInitialRetryOverride)) {
     factory_switches.backoff_override =
         EngineComponentsFactory::BACKOFF_SHORT_INITIAL_RETRY_OVERRIDE;
   }
   if (cl->HasSwitch(switches::kSyncEnableGetUpdateAvoidance)) {
     factory_switches.pre_commit_updates_policy =
         EngineComponentsFactory::FORCE_ENABLE_PRE_COMMIT_UPDATE_AVOIDANCE;
   }
+  if (cl->HasSwitch(switches::kSyncShortNudgeDelayForTest)) {
+    factory_switches.nudge_delay =
+        EngineComponentsFactory::NudgeDelay::SHORT_NUDGE_DELAY;
+  }
 
   std::map<ModelType, int64_t> invalidation_versions;
   sync_prefs_->GetInvalidationVersions(&invalidation_versions);
 
   std::unique_ptr<DoInitializeOptions> init_opts(new DoInitializeOptions(
       sync_thread_->message_loop(), registrar_.get(), workers,
       sync_client_->GetExtensionsActivity(), event_handler, sync_service_url,
       sync_user_agent, http_post_provider_factory_getter.Run(
                            core_->GetRequestContextCancelationSignal()),
       credentials, invalidator_ ? invalidator_->GetInvalidatorClientId() : "",
@@ skipping 683 matching lines @@
     const SyncManager::ClearServerDataCallback& frontend_callback) {
   DCHECK(ui_thread_->BelongsToCurrentThread());
   frontend_callback.Run();
 }
 
 }  // namespace syncer
 
 #undef SDVLOG
 
 #undef SLOG