Bug 122584 Cascading parameter values can't be displayed properly in html viewer.
Description: Cascading parameter values can't be displayed properly in html viewer. Steps to reproduce: 1. Preview attached design file in html viewer. 2. Click on "change parameter" button in html viewer. 3. Select the first parameter value and expect that the second parameter value in the same cascading parameter group could be displayed, but it is not displayed.
core/org.eclipse.birt.core/src/org/eclipse/birt/core/data/DataTypeUtil.java
* 		"false" -> false (ignore case)
	 * 		other string will throw an exception
	 * Date -> Boolean
	 * 		throw exception
	 * @param source
	 * @return
	 * @throws BirtException
	 */
	public static Boolean toBoolean( Object source ) throws BirtException
	{
		if ( source == null )
			return null;
		else if ( source instanceof Boolean )
		{
			return (Boolean) source;
		}
		else if ( source instanceof Integer )
		{
			int intValue = ( (Integer) source ).intValue( );
			if ( intValue == 0 )
				return new Boolean( false );
			return new Boolean( true );
		}
		else if ( source instanceof BigDecimal )
		{
			int intValue = ( (BigDecimal) source ).intValue( );
			if ( intValue == 0 )
				return new Boolean( false );
			return new Boolean( true );
		}