Bug 182673 No default value error message prompts incorrectly
Steps to reproduce: 1. New a report parameter; 2. Choose control type as Combo; 3. Choose parameter as dynamic type; Expected result: As the isRequired is false by default, parameter's default value can be null value. There should be no error message about no default value prompt. Actual result; Error messages prompts
UI/org.eclipse.birt.report.designer.ui/src/org/eclipse/birt/report/designer/ui/dialogs/CascadingParametersDialog.java
isRequired.setSelection( true );
	}
	private void setControlEnabled( boolean enable )
	{
		paramNameEditor.setEnabled( enable );
		promptText.setEnabled( enable );
		dataTypeChooser.setEnabled( enable );
		displayTypeChooser.setEnabled( enable );
		defaultValueChooser.setEnabled( enable );
		helpTextEditor.setEnabled( enable );
		formatField.setEnabled( enable );
		listLimit.setEnabled( enable );
		changeFormat.setEnabled( enable );
	}
	private void changeDataType( String type )
	{
		
		
		if ( type.equals( DesignChoiceConstants.PARAM_TYPE_STRING ) )
		{
			clearDefaultValueChooser( isRequired.getSelection( ) );
		}
		else
		{
			clearDefaultValueText( );
			clearDefaultValueChooserSelections( );
		}
		
		initFormatField( type );