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/MetaDataDictionary.java
* @param name
	 *            the internal name of the predefined style
	 * @return the predefined style, or null if the style is not defined
	 */
	public PredefinedStyle getPredefinedStyle( String name )
	{
		return (PredefinedStyle) predefinedStyles.get( name );
	}
	/**
	 * Determines if the meta data dictionary is empty (uninitialized).
	 * 
	 * @return true if empty, false if it contains content
	 */
	public boolean isEmpty( )
	{
		return elementNameMap.isEmpty( ) && predefinedStyles.isEmpty( );
	}
	/**
	 * Adds a choice set to the dictionary.
	 * 
	 * @param choiceSet
	 *            the choice set to add
	 * @throws MetaDataException
	 *             if the choice set is not valid
	 */
	void addChoiceSet( ChoiceSet choiceSet ) throws MetaDataException
	{
		String name = choiceSet.getName( );
		if ( StringUtil.isBlank( name ) )
			throw new MetaDataException(