[Sync] Move sessions/ to engine/cycle/ and rename things to match.

components/sync/engine_impl/cycle/nudge_tracker.h

Index: components/sync/engine_impl/cycle/nudge_tracker.h
diff --git a/components/sync/sessions_impl/nudge_tracker.h b/components/sync/engine_impl/cycle/nudge_tracker.h
similarity index 96%
rename from components/sync/sessions_impl/nudge_tracker.h
rename to components/sync/engine_impl/cycle/nudge_tracker.h
index 798a95e5905a1af71ec7773195947526f263e455..ef48b935e3edc0a8efae6c0d56ead9b0dc2955e9 100644
--- a/components/sync/sessions_impl/nudge_tracker.h
+++ b/components/sync/engine_impl/cycle/nudge_tracker.h
@@ -4,8 +4,8 @@
 //
 // A class to track the outstanding work required to bring the client back into
 // sync with the server.
-#ifndef COMPONENTS_SYNC_SESSIONS_IMPL_NUDGE_TRACKER_H_
-#define COMPONENTS_SYNC_SESSIONS_IMPL_NUDGE_TRACKER_H_
+#ifndef COMPONENTS_SYNC_ENGINE_IMPL_CYCLE_NUDGE_TRACKER_H_
+#define COMPONENTS_SYNC_ENGINE_IMPL_CYCLE_NUDGE_TRACKER_H_
 
 #include <stddef.h>
 
@@ -18,15 +18,13 @@
 #include "base/time/time.h"
 #include "components/sync/base/invalidation_interface.h"
 #include "components/sync/base/model_type.h"
+#include "components/sync/engine_impl/cycle/data_type_tracker.h"
 #include "components/sync/protocol/sync.pb.h"
-#include "components/sync/sessions_impl/data_type_tracker.h"
 
 namespace syncer {
 
 class ObjectIdInvalidationMap;
 
-namespace sessions {
-
 class NudgeTracker {
  public:
   static size_t kDefaultMaxPayloadsPerType;
@@ -203,7 +201,6 @@ class NudgeTracker {
   DISALLOW_COPY_AND_ASSIGN(NudgeTracker);
 };
 
-}  // namespace sessions
 }  // namespace syncer
 
-#endif  // COMPONENTS_SYNC_SESSIONS_IMPL_NUDGE_TRACKER_H_
+#endif  // COMPONENTS_SYNC_ENGINE_IMPL_CYCLE_NUDGE_TRACKER_H_