Problem:

Previously DML operations were cascaded recursively, between tables related
via foreign key constraints.  The patch in rb#2089 changed this recursive
approach to iterative approach by maintaining an explicit stack of update
nodes for cascading.  This patch did not take care of FTS operations, and
hence the current problem.

Note: The patch rb#2089 is for Bug #16244691 SERVER GONE AWAY ERROR OCCURS
DEPENDING ON THE NUMBER OF TABLE/KEY RELATIONS

Solution:

The FTS operations are now properly cascaded during iterative DML cascading
operations.

rb#8987 approved by Marko and Shaohua.