sync: Start moving away from PREV_ID and NEXT_ID

sync/syncable/syncable_util.cc

 // Copyright 2012 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 "sync/syncable/syncable_util.h"
 
 #include "base/base64.h"
 #include "base/location.h"
 #include "base/logging.h"
 #include "base/sha1.h"
@@ skipping 60 matching lines @@
       // maintain linked-list invariants).  In this case, NEXT_ID and PREV_ID
       // among the children will be valid after the loop, since we update all
       // the children at once.
       child_entry.PutParentIdPropertyOnly(new_id);
     }
   }
   // Update Id references on the previous and next nodes in the sibling
   // order.  Do this by reinserting into the linked list; the first
   // step in PutPredecessor is to Unlink from the existing order, which
   // will overwrite the stale Id value from the adjacent nodes.
-  if (entry->Get(PREV_ID) == entry->Get(NEXT_ID) &&
-      entry->Get(PREV_ID) == old_id) {
+  if (entry->GetPredecessorId() == entry->GetSuccessorId() &&
+      entry->GetPredecessorId() == old_id) {
     // We just need a shallow update to |entry|'s fields since it is already
     // self looped.
     entry->Put(NEXT_ID, new_id);
     entry->Put(PREV_ID, new_id);
   } else {
-    entry->PutPredecessor(entry->Get(PREV_ID));
+    entry->PutPredecessor(entry->GetPredecessorId());
   }
 }
 
 // Function to handle runtime failures on syncable code. Rather than crashing,
 // if the |condition| is false the following will happen:
 // 1. Sets unrecoverable error on transaction.
 // 2. Returns false.
 bool SyncAssert(bool condition,
                 const tracked_objects::Location& location,
                 const char* msg,
@@ skipping 15 matching lines @@
   serialized_type.AppendToString(&hash_input);
   hash_input.append(client_tag);
 
   std::string encode_output;
   CHECK(base::Base64Encode(base::SHA1HashString(hash_input), &encode_output));
   return encode_output;
 }
 
 }  // namespace syncable
 }  // namespace syncer