Bug 168808 Display text is lost after launching import values dialog
Steps to reproduce: 1.new a parameter; 2.select list box control type; 3.press "Import Values" button to import some values; 4.assign display texts for the imported values; 5.press "Import Values" button to launch import values dialog again; 6.press ok button on dialog; Expected result: The previous assigned display texts are remained. Actual result: The previous display texts are lost.
UI/org.eclipse.birt.report.designer.ui/src/org/eclipse/birt/report/designer/ui/dialogs/ParameterDialog.java
}
		}
		return false;
	}
	private void makeUniqueAndValid( )
	{
		for ( Iterator iter = choiceList.iterator( ); iter.hasNext( ); )
		{
			SelectionChoice choice = (SelectionChoice) iter.next( );
			if ( isValidValue( choice.getValue( ) ) != null
					|| containValue( choice, choice.getValue( ), COLUMN_VALUE ) )
			{
				iter.remove( );
			}
		}
	}
	private void changeControlType( )
	{
		if ( isStatic( ) )
		{
			String type = getSelectedControlType( );
			if ( !type.equals( lastControlType ) )
			{
				if ( DesignChoiceConstants.PARAM_CONTROL_CHECK_BOX.equals( type ) )
				{
					clearArea( valueArea );
					switchToCheckBox( );
				}
				else if ( PARAM_CONTROL_COMBO.equals( type )
						|| PARAM_CONTROL_LIST.equals( type )