Bug 141959 Changing data set didn't clean old column bindings
Steps to reproduce: 1.Add two data sets, "ds1" and "ds2" 2.Add a table, binding with "ds1". All "ds1" column bindings generate automatically, that's good 3.Change "ds1" to None Expected result: All "ds1" column bindings should be cleaned Actual result: All "ds1" column bindings are still there. If changing to "ds2", "ds2" column bindings will be added after them.
UI/org.eclipse.birt.report.designer.ui/src/org/eclipse/birt/report/designer/ui/dialogs/ColumnBindingDialog.java
Composite parentComposite = (Composite) super.createDialogArea( parent );
		if ( this.canSelect )
		{
			/**
			 * Label & button
			 */
			Composite composite = new Composite( parentComposite, SWT.NONE );
			composite.setLayoutData( new GridData( GridData.FILL_HORIZONTAL ) );
			composite.setLayout( UIUtil.createGridLayoutWithoutMargin( 2, false ) );
			CLabel warnLabel = new CLabel( composite, SWT.NONE );
			warnLabel.setImage( PlatformUI.getWorkbench( )
					.getSharedImages( )
					.getImage( ISharedImages.IMG_OBJS_WARN_TSK ) );
			warnLabel.setText( WARN_COLUMN_BINDINGS );
			GridData gd = new GridData( GridData.FILL_HORIZONTAL );
			gd.horizontalSpan = 2;
			warnLabel.setLayoutData( gd );
			Label label = new Label( composite, SWT.NONE );
			label.setText( LABEL_COLUMN_BINDINGS );
			label.setLayoutData( new GridData( GridData.BEGINNING ) );
			
			final CCombo combo = new CCombo( composite, SWT.READ_ONLY
					| SWT.BORDER );
			combo.setBackground( PlatformUI.getWorkbench( )
					.getDisplay( )
					.getSystemColor( SWT.COLOR_LIST_BACKGROUND ) );
			String[] dataSets = ChoiceSetFactory.getDataSets( );
			String[] newList = new String[dataSets.length + 1];
			newList[0] = NONE;
			System.arraycopy( dataSets, 0, newList, 1, dataSets.length );