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/metadata/ElementPropertyDefn.java
if ( groupNameKey == null )
			return null;
		return ModelMessages.getMessage( groupNameKey );
	}
	/**
	 * Indicates if derived elements can inherit the value of this property.
	 * Most properties can inherit values from a parent element. A few system
	 * properties, such as the name or extends, can't be inherited.
	 * <p>
	 * Note: This attribute is used for both style property and non-style
	 * property with two different meanings.
	 * <ul>
	 * <li>For style property, it determines whether this property can be
	 * cascaded from container;
	 * <li>For non-style property, that means whether this property can be
	 * inherited from parent.
	 * </ul>
	 * We take it because of the fact style is not inheritable, and the
	 * following diagram:
	 * <p>
	 * <table border="1" cellpadding="2" cellspacing="2" style="border-collapse:
	 * collapse" bordercolor="#111111">
	 * <th width="20%"></th>
	 * <th width="40%">can inherit</th>
	 * <th width="40%">can cascade</th>
	 * <tr>
	 * <td>Style property</td>
	 * <td align="center"><code>false</code></td>
	 * <td align="center"><code>isInheritable</code></td>
	 * </tr>