Bug 134954 Library can't be removed
Steps to reproduce: 1.New a report "a.rptdesign" 2.New a library which is not in the same fold with report, saying "../test/lib.rptlibrary" 3.Report includes the library 4.Remove the library Expected result: The library is removed Actual result: Open XMLSource, the included library structure is still there.
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/command/LibraryCommand.java
*/
	private void doDropLibrary( Library library ) throws SemanticException
	{
		
		ActivityStack stack = getActivityStack( );
		stack.startTrans( );
		
		LibraryRecord record = new LibraryRecord( module, library, false );
		getActivityStack( ).execute( record );
		try
		{
			String libFileName = library.getFileName( );
			assert libFileName != null;
			removeIncludeLibrary( libFileName, library.getNamespace( ) );
		}
		catch ( SemanticException ex )
		{
			stack.rollback( );
			throw ex;
		}
		getActivityStack( ).commit( );
	}
	/**
	 * Checks possible extends references for the given element. If extends
	 * reference is unresolve, virtual elements of extends children are removed.
	 * And local property values of virtual elements are returned.
	 * 
	 * @param parent
	 *            the design element
	 * @return the map containing local values of virtual elements. Each key is