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
* Default locale of the validation issues. If the caller does not provide
	 * the locale information, we will use it.
	 */
	private static final ULocale DEFAULT_LOCALE = ULocale.US;
	/**
	 * Default date-time format string.
	 */
	public static final String DEFAULT_DATETIME_FORMAT = "MM/dd/yyyy hh:mm:ss a"; 
	/**
	 * Validates a input parameter value with the given data type. The returned
	 * value is locale and format independent. The data type can be one of the
	 * following:
	 * 
	 * <ul>
	 * <li><code>PARAM_TYPE_DATETIME</code></li>
	 * <li><code>PARAM_TYPE_FLOAT</code></li>
	 * <li><code>PARAM_TYPE_DECIMAL</code></li>
	 * <li><code>PARAM_TYPE_BOOLEAN</code></li>
	 * <li><code>PARAM_TYPE_STRING</code></li>
	 * </ul>
	 * 
	 * @param dataType
	 *            the data type of the value
	 * @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
	 * @throws ValidationValueException