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
if ( value == null || value.length( ) == 0 )
		{
			return ERROR_MSG_CANNOT_BE_NULL;
		}
		if ( canBeBlank( ) )
		{
			if ( StringUtil.isBlank( value ) )
			{
				return null;
			}
		}
		else
		{
			if ( StringUtil.isBlank( value ) )
			{
				return ERROR_MSG_CANNOT_BE_BLANK;
			}
		}
		try
		{
			getValue( value );
		}
		catch ( BirtException e )
		{
			return ERROR_MSG_MISMATCH_DATA_TYPE;