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
}
			else
			{
				namespace = null;
			}
		}
		return namespace;
	}
	public static ThemeHandle themeInModuleHandle( ThemeHandle handle,
			ModuleHandle moduleHandle )
	{
		String themeName = handle.getName( ).trim( );
		String themeFileName = handle.getModuleHandle( ).getFileName( );
		LibraryHandle libHandle = moduleHandle.findLibrary( themeFileName );
		if ( libHandle == null )
		{
			return null;
		}
		Iterator iterator = moduleHandle.getVisibleThemes( IAccessControl.DIRECTLY_INCLUDED_LEVEL )
				.iterator( );
		if ( iterator != null )
		{
			while ( iterator.hasNext( ) )
			{
				ReportElementHandle elementHandle = (ReportElementHandle) iterator.next( );
				if ( elementHandle.getName( ).trim( ).equals( themeName )
						&& elementHandle.getRoot( ) == libHandle )
				{
					return (ThemeHandle) elementHandle;
				}