Bug 175664 [Mac] Unexpected internal exception occurs when invoke expression builder
Description: There are two problems: 1. "fx" button (Click this button to invoke Expression Builder) could not be displayed correctly, nothing displayed in the button. 2. Click on the button, an unexpected internal exception occurs. Version:2.2.0.v20070205 Steps to reproduce: 1.Insert a Data item to the layout. Click "fx" button to invoke the expression builder, although on Mac "fx" button could not display correctly. Error log: Argument cannot be null Plug-in Provider: Eclipse.org Plug-in Name: BIRT Designer UI Plug-in ID: org.eclipse.birt.report.designer.ui Error Code: Error.GUIException.invokedByUnexpectedException Error Message:Argument cannot be null
UI/org.eclipse.birt.report.designer.ui/src/org/eclipse/birt/report/designer/internal/ui/util/UIUtil.java
{
			return null;
		}
		URL url = bundle.getEntry( "/" ); 
		if ( url == null )
		{
			return null;
		}
		String directory = null;
		try
		{
			directory = FileLocator.resolve( url ).getPath( );
		}
		catch ( IOException e )
		{
			logger.log(Level.SEVERE, e.getMessage(),e);
		}
		return directory;
	}
	/**
	 * Creates a blank label under the given parent.
	 * 
	 * @return the label created
	 */
	public static Label createBlankLabel( Composite parent )
	{
		Label label = new Label( parent, SWT.NONE );
		label.setVisible( false );
		return label;
	}