Single Line Cells Repeating Thead Starts Middle Of Page Break After Avoid Expected

crbug.com/624814: A table header group should not repeat on each page if we can't fit at least one content row below it.

| Col 1 | Col 2 | | Te | xt | | Te | xt | | Te | xt | | Te | xt | | Te | xt | | Te | xt | | Te | xt | | Col 1 | Col 2 | | Te | xt | | Te | xt | | Te | xt | | Te | xt | | Te | xt | | Te | xt | | Te | xt | | Col 1 | Col 2 | | Te | xt | | Te | xt | | Te | xt | | Te | xt | | Te | xt | | Te | xt | | Te | xt | | Te | xt | | Te | xt |