[Sync] Don't commit items with predecessors/parents in conflict.

chrome/browser/sync/engine/build_commit_command.cc

 // Copyright (c) 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 "chrome/browser/sync/engine/build_commit_command.h"
 
 #include <limits>
 #include <set>
 #include <string>
 #include <vector>
@@ skipping 186 matching lines @@
         } else {
           position_block = std::make_pair(
               FindAnchorPosition(syncable::PREV_ID, meta_entry),
               FindAnchorPosition(syncable::NEXT_ID, meta_entry));
         }
         position_block.first = InterpolatePosition(position_block.first,
                                                    position_block.second);
 
         position_map[id] = position_block;
         sync_entry->set_position_in_parent(position_block.first);
+        DVLOG(1) << "Setting server position for entry "
+                 << meta_entry.Get(syncable::ID)
+                 << " from "
+                 << meta_entry.Get(syncable::SERVER_POSITION_IN_PARENT)
+                 << " to " << position_block.first;
       }
       SetEntrySpecifics(&meta_entry, sync_entry);
     }
   }
   session->mutable_status_controller()->
       mutable_commit_message()->CopyFrom(message);
 
   return SYNCER_OK;
 }
 
@@ skipping 29 matching lines @@
   if (delta <= static_cast<uint64>(GetGap()*2))
     return lo + (static_cast<int64>(delta) + 7) / 8;  // Interpolate.
   else if (lo == GetFirstPosition())
     return hi - GetGap();  // Extend range just before successor.
   else
     return lo + GetGap();  // Use or extend range just after predecessor.
 }
 
 
 }  // namespace browser_sync