Bug 164070 Support widows/orphans properties on text item
Support widows/orphans properties on block text item(label, text, data etc), About the definition of widows/orphans, please refer to CSS spec.
model/org.eclipse.birt.report.model.tests/test/org/eclipse/birt/report/model/api/DesignElementHandleTest.java
* </tr>
 * 
 * <tr>
 * <td></td>
 * <td>Whether the label and grid can be contained in the freeform slot before
 * and after inserting in the slot.</td>
 * <td>The return value is true before/after inserting.</td>
 * </tr>
 * 
 * <tr>
 * <td>{@link #testCanContainTableHeader()}</td>
 * <td>DataSets slot in the design can contain only data-sets without any
 * data-source.</td>
 * <td>The return values are expected.</td>
 * </tr>
 * <tr>
 * <td></td>
 * <td>The slot in a free-form can contain list, table, etc. But not any cell,
 * data-set, etc..</td>
 * <td>The return values are expected.</td>
 * </tr>
 * <tr>
 * <td></td>
 * <td>Any slot cannot contain <code>null</code> elements.</td>
 * <td>The return values are expected.</td>
 * </tr>
 * 
 * <tr>
 * <td>{@link #testGetPath()}</td>
 * <td>The path of a label in the body slot.</td>