| Index: sync/test/engine/syncer_command_test.h
 | 
| diff --git a/sync/test/engine/syncer_command_test.h b/sync/test/engine/syncer_command_test.h
 | 
| index fa51d8221d2169fc9cfbaa31e6052e1e128d821d..1a8f4b83ea236e8c27dc18b19fe3e957572fcc43 100644
 | 
| --- a/sync/test/engine/syncer_command_test.h
 | 
| +++ b/sync/test/engine/syncer_command_test.h
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| @@ -107,7 +107,13 @@ class SyncerCommandTestBase : public testing::Test,
 | 
|  
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|    // Create a session with the provided source.
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|    sessions::SyncSession* session(const sessions::SyncSourceInfo& source) {
 | 
| -    if (!session_) {
 | 
| +    // These sources require a valid nudge tracker.
 | 
| +    DCHECK_NE(sync_pb::GetUpdatesCallerInfo::LOCAL, source.updates_source);
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| +    DCHECK_NE(sync_pb::GetUpdatesCallerInfo::NOTIFICATION,
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| +              source.updates_source);
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| +    DCHECK_NE(sync_pb::GetUpdatesCallerInfo::DATATYPE_REFRESH,
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| +              source.updates_source);
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| +    if (!session_.get()) {
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|        std::vector<ModelSafeWorker*> workers = GetWorkers();
 | 
|        session_.reset(new sessions::SyncSession(context(), delegate(), source));
 | 
|      }
 | 
| 
 |