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

components/sync/engine_impl/get_commit_ids.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/engine_impl/get_commit_ids.h"
 
 #include <stddef.h>
 #include <stdint.h>
 
 #include <set>
@@ skipping 40 matching lines @@
                     std::vector<int64_t>* out);
 
 }  // namespace
 
 void GetCommitIdsForType(syncable::BaseTransaction* trans,
                          ModelType type,
                          size_t max_entries,
                          syncable::Directory::Metahandles* out) {
   syncable::Directory* dir = trans->directory();
 
-  // Gather the full set of unsynced items and store it in the session. They
+  // Gather the full set of unsynced items and store it in the cycle. They
   // are not in the correct order for commit.
   std::set<int64_t> ready_unsynced_set;
   syncable::Directory::Metahandles all_unsynced_handles;
   GetUnsyncedEntries(trans, &all_unsynced_handles);
 
   ModelTypeSet encrypted_types;
   bool passphrase_missing = false;
   Cryptographer* cryptographer = dir->GetCryptographer(trans);
   if (cryptographer) {
     encrypted_types = dir->GetNigoriHandler()->GetEncryptedTypes(trans);
@@ skipping 500 matching lines @@
   // Add moves and creates, and prepend their uncommitted parents.
   traversal.AddCreatesAndMoves(ready_unsynced_set);
 
   // Add all deletes.
   traversal.AddDeletes(ready_unsynced_set);
 }
 
 }  // namespace
 
 }  // namespace syncer