Fix missing/broken ds.Stop handling in raw DS.

filter/txnBuf/query_merger.go

 // Copyright 2015 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.
 
 package txnBuf
 
 import (
         "bytes"
         "sort"
 
@@ skipping 217 matching lines @@
                 if distinct != nil {
                         // NOTE: We know that toUse will not be used after this point for
                         // comparison purposes, so re-use its cmpRow property for our distinct
                         // filter here.
                         toUse.cmpRow = ""
                         if !distinct.Add(toUse.getCmpRow(nil, nil, distinctOrder)) {
                                 continue
                         }
                 }
                 if err := cb(toUse.key, toUse.data); err != nil {
-                        if err == ds.Stop {
-                                return nil
-                        }
                         return err
                 }
         }
 
         return nil
 }
 
 // toComparableString computes the byte-sortable 'order' string for the given
 // key/PropertyMap.
 //
@@ skipping 41 matching lines @@
                 }
                 if !foundOne {
                         return nil, nil
                 }
         }
         if end != nil && bytes.Compare(soFar, end) >= 0 {
                 return nil, nil
         }
         return soFar, ps["__key__"][0]
 }