Bug 130495 Get rid of SessionHandleAdapter
Now, we use SessionHandleAdapter to keep current active report deisng. That's a bad practive for editor swith and rebuild will cuase lots of problmes. Need find way to replace it.
UI/org.eclipse.birt.report.designer.core/src/org/eclipse/birt/report/designer/core/model/SessionHandleAdapter.java
public ReportMediator getMediator( )
	{
		return getMediator( getReportDesignHandle( ) );
	}
	/**
	 * @param oldObj
	 *            old model
	 * @param newObj
	 *            new model
	 */
	public void resetReportDesign( Object oldObj, Object newObj )
	{
		ReportMediator mediator = (ReportMediator) mediatorMap.get( oldObj );
		if ( mediator == null )
		{
			return;
		}
		mediatorMap.remove( oldObj );
		mediatorMap.put( newObj, mediator );
	}
	public void clear(ModuleHandle handle )
	{
		mediatorMap.remove( handle );
		if(handle == getReportDesignHandle( ))
		{
			setReportDesignHandle( null );
			designHandleAdapter = null;
		}
	}
}