[Sync] Move events files around a bit.

components/sync/engine_impl/events/poll_get_updates_request_event.h

Index: components/sync/engine_impl/events/poll_get_updates_request_event.h
diff --git a/components/sync/engine/events/poll_get_updates_request_event.h b/components/sync/engine_impl/events/poll_get_updates_request_event.h
similarity index 83%
rename from components/sync/engine/events/poll_get_updates_request_event.h
rename to components/sync/engine_impl/events/poll_get_updates_request_event.h
index 12b2542847f1881a9dd543bb849e0c463dfb9ef4..be7e0d1b323d6ef5713e4fc075b53090e6b21eef 100644
--- a/components/sync/engine/events/poll_get_updates_request_event.h
+++ b/components/sync/engine_impl/events/poll_get_updates_request_event.h
@@ -2,8 +2,8 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#ifndef COMPONENTS_SYNC_ENGINE_EVENTS_POLL_GET_UPDATES_REQUEST_EVENT_H_
-#define COMPONENTS_SYNC_ENGINE_EVENTS_POLL_GET_UPDATES_REQUEST_EVENT_H_
+#ifndef COMPONENTS_SYNC_ENGINE_IMPL_EVENTS_POLL_GET_UPDATES_REQUEST_EVENT_H_
+#define COMPONENTS_SYNC_ENGINE_IMPL_EVENTS_POLL_GET_UPDATES_REQUEST_EVENT_H_
 
 #include <memory>
 #include <string>
@@ -41,4 +41,4 @@ class PollGetUpdatesRequestEvent : public ProtocolEvent {
 
 }  // namespace syncer
 
-#endif  // COMPONENTS_SYNC_ENGINE_EVENTS_POLL_GET_UPDATES_REQUEST_EVENT_H_
+#endif  // COMPONENTS_SYNC_ENGINE_IMPL_EVENTS_POLL_GET_UPDATES_REQUEST_EVENT_H_