Bug 112287 It's better to transfer to "new data source" dialog when creating a new data set without existing data source.
Description: It's better to transfer to "new data source" dialog automatically when creating a new data set without existing data source. Steps to reproduce: 1. There is no existing data source. 2. Create a new data set. 3. It pops up hint message, saying that "there is no data source". Actual result: it's better to transfer to "new data source" dialog box now and help users create a new data source.
chart/org.eclipse.birt.chart.reportitem.ui/src/org/eclipse/birt/chart/reportitem/ui/ReportDataServiceProvider.java
{
	private ExtendedItemHandle itemHandle;
	/**
	 * This flag indicates whether the error is found when fetching data. This
	 * is to help reduce invalid query.
	 */
	private boolean isErrorFound = false;
	public ReportDataServiceProvider( ExtendedItemHandle itemHandle )
	{
		super( );
		this.itemHandle = itemHandle;
	}
	private ModuleHandle getReportDesignHandle( )
	{
		return itemHandle.getModuleHandle( );
	}
	public String[] getAllDataSets( )
	{
		List list = getReportDesignHandle( ).getVisibleDataSets( );
		String[] names = new String[list.size( )];
		for ( int i = 0; i < names.length; i++ )
		{
			names[i] = ( (DataSetHandle) list.get( i ) ).getQualifiedName( );
		}
		return names;
	}
	public final String[] getPreviewHeader( ) throws ChartException
	{
		Iterator iterator = ReportItemUIUtil.getColumnDataBindings( itemHandle );