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
{
			try
			{
				return Double.valueOf( (String) source );
			}
			catch ( NumberFormatException e )
			{
				throw new BirtException( pluginId, ResourceConstants.CONVERT_FAILS,
						"Double", resourceBundle );
			}
		}
		else
			throw new BirtException( pluginId, ResourceConstants.CONVERT_FAILS, "Double",
					resourceBundle );
	}
	/**
	 * Number -> String
	 * 		Number.toString()
	 * Boolean -> String
	 * 		Boolean.toString()
	 * Date	-> String
	 * 		toString(Date)
	 * @param source
	 * @return
	 * @throws BirtException
	 */
	public static String toString( Object source ) throws BirtException
	{
		return toString( source, Locale.getDefault( ) );
	}