grid with setSummaryRowDataSource() fetches summary row multiple times on viewState

[michalg]

1. SmartClient Version: v10.0p_2015-04-22/LGPL Development Only (built 2015-04-22)
2. Firefox 24.8.0 on gentoo linux

Hi,
This is striped down test case with basic ListGrid displaying summary row, but summary record is requested from DataSource via lg.setSummaryRowDataSource(ds);

package pl.com.tech4.client;

import com.google.gwt.core.client.EntryPoint;
import com.google.gwt.user.client.DOM;
import com.smartgwt.client.data.DataSourceField;
import com.smartgwt.client.data.RestDataSource;
import com.smartgwt.client.data.fields.DataSourceFloatField;
import com.smartgwt.client.data.fields.DataSourceTextField;
import com.smartgwt.client.util.SC;
import com.smartgwt.client.widgets.IButton;
import com.smartgwt.client.widgets.events.ClickEvent;
import com.smartgwt.client.widgets.events.ClickHandler;
import com.smartgwt.client.widgets.grid.ListGrid;
import com.smartgwt.client.widgets.layout.VLayout;

public class MainEntryPoint implements EntryPoint {
   
    public void onModuleLoad() {

        DOM.getElementById("loadingPicture").removeFromParent();
        layout();
        SC.showConsole();
    }
   
    private void layout() {
        RestDataSource ds = new RestDataSource();
        ds.setDataURL("UnitDir.xml");
        DataSourceField fieldId = new DataSourceField();
        fieldId.setName("id");
        fieldId.setPrimaryKey(true);
        fieldId.setHidden(true);
        DataSourceTextField fieldCode = new DataSourceTextField();
        fieldCode.setName("code");
        DataSourceFloatField fieldValue = new DataSourceFloatField();
        fieldValue.setName("value");
        ds.setFields(fieldId, fieldCode, fieldValue);
       
        final ListGrid lg = new ListGrid();
        lg.setDataSource(ds);
        lg.setAutoFetchData(true);
        lg.setShowGridSummary(true);
        lg.setSummaryRowDataSource(ds);
       
        IButton button = new IButton("test");
        button.addClickHandler(new ClickHandler() {

            public void onClick(ClickEvent event) {
                lg.setViewState(lg.getViewState());
            }
        });

        VLayout layout = new VLayout();
        layout.addMember(lg);
        layout.addMember(button);
       
        layout.draw();
       
    }
   
}

UnitDir.xml:

<response>
    <status>STATUS_SUCCESS</status>
    <startRow>0</startRow>
    <endRow>1</endRow>
    <totalRows>1</totalRows>
    <data>
        <UnitDir>
            <id>1</id>
            <code>kg</code>
            <value>5</value>
        </UnitDir>
    </data>
</response>

Running this example shows two requests/responses on the RPC tab: one for fetching grid's data and the second one fetching summary row. So far so good.
Now, pressing test button, which only resets viewState of the grid:
lg.setViewState(lg.getViewState());
shows identical 3 new requests/responses on RPC tab, each fetching summary record again and again.

Could it be corrected, as it stresses server in a real application (aggregation is sql costly).
Thanks,
MichalG