Resolves: #i119954# fix nest tables to text conversion crash
Resolves: #i119954# fix nest tables to text conversion crash

- assure that conversion of nested tables are performed correctly.

Found by: Yang Ji <yanji.yj at gmail dot com>
Patch by: kang jian <jane73_kang at hotmail dot com>
Review by: Oliver <orw at apache dot org>
(cherry picked from commit 48538700cdafaa4becfe74a1d3d93179aed9d764)

Change-Id: Iaefbf6f75d526ef8c0c4302d8b39096becc183e8

JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core