Fix a couple of recently introduced issues with Table metadata.
Fix a couple of recently introduced issues with Table metadata.

parthea/datalab,craigcitro/datalab,googledatalab/datalab,yebrahim/datalab,yebrahim/datalab,craigcitro/datalab,googledatalab/datalab,yebrahim/datalab,parthea/datalab,craigcitro/datalab,parthea/datalab,googledatalab/datalab,craigcitro/datalab,craigcitro/datalab,googledatalab/datalab,googledatalab/datalab,parthea/datalab,yebrahim/datalab,parthea/datalab,yebrahim/datalab,parthea/datalab,googledatalab/datalab