Fix occasional empty rows in Table and TreeTable (#9800)

Fix occasional empty rows in Table and TreeTable (#9800)

Picked from #9551 in 7.7

There's an intermittently happening issue with both Table and TreeTable,
which results in row data disappearing.
This change removes a method which is probably a vestigial one from over
five years ago and other changes are handling the things the method used
to perform. Currently the method removes rows deemed unnecessary from
the row buffer. The problem is, those rows are visible to the user and
removing causes row contents to be lost.
Also included are manually runnable test cases which demonstrate that
this removal actually prevents the issue from happening.

Fixes #7964
Fixes #5030