Bug 153391 Some Options in Edit Parameter dialog haven't been saved.
Description: Some Options in Edit Parameter dialog haven't been saved. Steps to reproduce: 1. new a parameter, boolean type, tick AllowNUll and sort alphabetically... 2. Close the dialog and reopen it. 3. new a parameter, string, combo-box, tick AllowNull. 4. Close the dialog and reopen it. Expected result: Ticked options' status are saved Actual result: After reopen parameter dialog, options are unticked.
UI/org.eclipse.birt.report.designer.ui/src/org/eclipse/birt/report/designer/ui/dialogs/ParameterDialog.java
{
			IChoice choice = dataType.findChoiceByDisplayName( dataTypeChooser.getText( ) );
			type = dataType.findChoiceByDisplayName( dataTypeChooser.getText( ) )
					.getName( );
			type = choice.getName( );
		}
		return type;
	}
	/**
	 * Gets the internal name of the control type from the display name
	 */
	private String getSelectedControlType( )
	{
		String displayText = controlTypeChooser.getText( );
		if ( StringUtil.isBlank( displayText ) )
		{
			return getInputControlType( );
		}
		if ( DISPLAY_NAME_CONTROL_COMBO.equals( displayText ) )
		{
			return PARAM_CONTROL_COMBO;
		}
		if ( DISPLAY_NAME_CONTROL_LIST.equals( displayText ) )
		{
			return PARAM_CONTROL_LIST;
		}
		return controlType.findChoiceByDisplayName( displayText ).getName( );
	}
	private void changeDataType( )
	{