Bug 145520 Group name will not show up in group list if the group use default name and key expression has no value
Description: Group name will not show up in group list if key expression has no value. Steps to reproduce: 1. Insert a table into report, bind it to a data set 2. Switch to property editor -> groups 3. Click on add button to open new group dialog, then press ok button Expected result: A new group with default name will be added to group list Actual result: A new group is added to group list, but without group name. But when let group tab lost focus and get focus again, you can see the group name.
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/core/Module.java
libraries = new ArrayList( );
		
		assert posn >= 0 && posn <= libraries.size( );
		libraries.add( posn, library );
	}
	/**
	 * Adds the given libray to library list.
	 * 
	 * @param library
	 *            the library to insert
	 */
	public void addLibrary( Library library )
	{
		if ( libraries == null )
			libraries = new ArrayList( );
		libraries.add( library );
	}
	/**
	 * Drops the given library from library list.
	 * 
	 * @param library
	 *            the library to drop
	 * @return the position of the library to drop
	 */
	public int dropLibrary( Library library )
	{
		assert libraries != null;
		assert libraries.contains( library );
		int posn = libraries.indexOf( library );
		libraries.remove( library );