Bug 134988 [regression]Available items in Query didn't change when change data source in Edit Data Set Dialog.
Description: Available items in Query didn't change when change data source in Edit Data Set Dialog. Steps to reproduce: 1. New two different data sources. 2. New a dataset, change data source, view Available Items in Query pane. Expected result: Available Items in Query pane changed according to new Data source. Actual result: Available Items in Query pane kept unchanged.
UI/org.eclipse.birt.report.designer.ui/src/org/eclipse/birt/report/designer/data/ui/property/AbstractPropertyDialog.java
sashForm.setLayoutData( new GridData( GridData.FILL_BOTH ) );
		createTreeViewer( sashForm );
		createPropertyPane( sashForm );
		sashForm.setWeights( new int[]{20, 80} );
		Label label = new Label( composite, SWT.HORIZONTAL | SWT.SEPARATOR );
		label.setLayoutData( new GridData( GridData.FILL_HORIZONTAL ) );
		initTreeSelection( );
		return composite;
	}
	/**
	 * For the first node of tree is not default selected as it is under
	 * Windows, this method set the first node to be selected for Linux.
	 */
	private void initTreeSelection( )
	{
		PropertyNode node = getNode( getDeafultNode( ) );
		if ( node != null )
		{
			StructuredSelection select = new StructuredSelection( node );
			viewer.setSelection( select );
		}
		else
		{
			if(viewer.getTree( ).getItems( ).length>0)
			{
				TreeItem firstNode = viewer.getTree( ).getItems( )[0];
				StructuredSelection select = new StructuredSelection( firstNode.getData( ) );
				viewer.setSelection( select );
			}
		}