code: public static ImageDescriptor getDescriptor(String key)
  	{
  		if (fgImageRegistry == null)
  		{
  			return fgAvoidSWTErrorMap.get(key);
  		}
  		return getImageRegistry().getDescriptor(key);
  	}
docs: Returns the image descriptor for the given key in this registry. Might be called in a non-UI thread.
  
  @param key
  the image's key
  @return the image descriptor for the given key