Bug 156497 [Regression][Acceptance]Report isn't refreshed when delete used library file.
Description: Report isn't refreshed when delete used library file. Steps to reproduce: 1.New a library, add a label, input actuate. 2.New a report, extend lib.label 3.Delete the library file. 4.Refresh the report in Outline of the report Expected result: Empty label in Layout. Actual result: label with content "actuate" in Layout.
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/api/ModuleHandle.java
* Sets the default units for the design. These are the units that are used
	 * for dimensions that don't explicitly specify units.
	 * <p>
	 * 
	 * For a report design, it allows the following constants that defined in
	 * <code>{@link org.eclipse.birt.report.model.api.elements.DesignChoiceConstants}</code>:
	 * <ul>
	 * <li><code>UNITS_IN</code></li>
	 * <li><code>UNITS_CM</code></li>
	 * <li><code>UNITS_MM</code></li>
	 * <li><code>UNITS_PT</code></li>
	 * </ul>
	 * 
	 * @param units
	 *            the default units for the design.
	 * @throws SemanticException
	 *             if the input unit is not one of allowed.
	 * 
	 * @see org.eclipse.birt.report.model.api.metadata.DimensionValue
	 */
	public void setDefaultUnits( String units ) throws SemanticException
	{
		setStringProperty( UNITS_PROP, units );
	}
	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.birt.report.model.api.DesignElementHandle#getElement()
	 */
	public DesignElement getElement( )