Bug 153378 [Regression]Label text won't show up when the text key is not found
Steps to reproduce: 1.Add a label, set text to "aaa" 2.Add a resource file "a" to the report, add a text key "k1" which is not in the a.properties to the label 3.Preview in Web Viewer Expected result: Label display "aaa" when the text key is not found Actual result: Nothing in preview
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/api/util/ParameterValidationUtil.java
* <li>pattern string, such as "lt!" and so on.</li>
	 * </ul>
	 * </td>
	 * </tr>
	 * </table>
	 * 
	 * @param dataType
	 *            the data type of the value
	 * @param format
	 *            the format choice string
	 * @param value
	 *            the input value to validate
	 * @param locale
	 *            the locale information
	 * @return the validated value if the input value is valid for the given
	 *         data type and format choice string
	 * @throws ValidationValueException
	 *             if the input value is not valid with the given data type and
	 *             format string
	 */
	static public Object validate( String dataType, String format,
			String value, ULocale locale ) throws ValidationValueException
	{
		if ( value == null )
			return null;
		if ( StringUtil.isBlank( format ) )
			return validate( dataType, value, locale );
		try
		{
			if ( DesignChoiceConstants.PARAM_TYPE_DATETIME