Bug 153040 Template definition should be removed after the report item is deleted
Steps to reproduce: 1.New a report, extends lib.label 2.Convert the label to template report item, and revert it back to the report item 3.Delete the label 4.Remove the included library Expected result: Library can be removed Actual result: A BIRT exception occurred. Plug-in Provider:Eclipse.org Plug-in Name:BIRT Model Plug-in ID:org.eclipse.birt.report.model Version:2.1.0.v20060808-0630 Error Code:Error.LibraryException.LIBRARY_HAS_DESCENDENTS Error Message:The library "Lib" can no be dropped because it has descendents "NewLabel" in the current module.
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/command/ContentCommand.java
* in a container. Containers are identified by a container ID. The
	 * application creates the element object, then adds it to the container
	 * here. The undo of this operation effectively deletes the element.
	 * 
	 * @param content
	 *            the element to add
	 * @param slotID
	 *            the slot in which to add the component
	 * @throws ContentException
	 *             if the content cannot be added into this container.
	 * @throws NameException
	 *             if the name of the content exists in name space.
	 */
	public void add( DesignElement content, int slotID )
			throws ContentException, NameException
	{
		doAdd( content, slotID, -1 );
	}
	/**
	 * Adds a new element into a container. Virtually all elements must reside
	 * in a container. (The term "container" here is generic, it is not the same
	 * as the Container element defined in the XML schema.) Containers are
	 * identified by a container ID. The application creates the element object,
	 * then adds it to the container here. The undo of this operation
	 * effectively deletes the element.
	 * 
	 * @param content
	 *            the element to add
	 * @param slotID
	 *            the slot in which to add the component