[Sync] Support commit only types.

components/sync/engine_impl/cycle/nudge_tracker.cc

 // Copyright (c) 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/engine_impl/cycle/nudge_tracker.h"
 
 #include <algorithm>
 #include <utility>
 
 #include "base/memory/ptr_util.h"
 #include "components/sync/engine/polling_constants.h"
 
 namespace syncer {
 
 namespace {
 
 // Delays for syncer nudges.
 const int kDefaultNudgeDelayMilliseconds = 200;
 const int kSlowNudgeDelayMilliseconds = 2000;
 const int kSyncRefreshDelayMilliseconds = 500;
 const int kSyncSchedulerDelayMilliseconds = 250;
 
 base::TimeDelta GetDefaultDelayForType(ModelType model_type,
                                        base::TimeDelta minimum_delay) {
   switch (model_type) {
     case AUTOFILL:
+    case USER_EVENTS:
       // Accompany types rely on nudges from other types, and hence have long
       // nudge delays.
       return base::TimeDelta::FromSeconds(kDefaultShortPollIntervalSeconds);
     case BOOKMARKS:
     case PREFERENCES:
     case SESSIONS:
     case FAVICON_IMAGES:
     case FAVICON_TRACKING:
       // Types with sometimes automatic changes get longer delays to allow more
       // coalescing.
@@ skipping 376 matching lines @@
           GetDefaultDelayForType(type, minimum_local_nudge_delay_));
     }
   }
 }
 
 void NudgeTracker::SetDefaultNudgeDelay(base::TimeDelta nudge_delay) {
   minimum_local_nudge_delay_ = nudge_delay;
 }
 
 }  // namespace syncer