Bug 195607 NPE is thrown when calling DimensionHandle:: getAbsoluteValue()
If a DimensionHandle did not set DimensionValue, NPE will thrown when calling DimensionHandle:: getAbsoluteValue().
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/api/DimensionHandle.java
/**
	 * Sets the value of a dimension in default units. The default unit may be
	 * defined by the property in BIRT or the application unit defined in the
	 * design session.
	 * 
	 * @param value
	 *            the new value in application units.
	 * @throws SemanticException
	 *             if the property is locked
	 */
	public void setAbsolute( double value ) throws SemanticException
	{
		setValue( new Double( value ) );
	}
	/**
	 * Returns the absolute dimension value with the following units.
	 * <ul>
	 * <li>UNITS_IN
	 * <li>UNITS_CM
	 * <li>UNITS_MM
	 * <li>UNITS_PT
	 * <li>UNITS_PC
	 * <li>UNITS_PX
	 * </ul>
	 * 
	 * This method tries to get the absolute value for absolute font size
	 * constants with {@link IAbsoluteFontSizeValueProvider}. Only the value of
	 * CSS property of the element which is not style is handled here.
	 * <code>null</code> is returned if this dimension is not CSS style
	 * property.