use UNDO_EMPTY instead of bare 0
use UNDO_EMPTY instead of bare 0

Change-Id: Ida0b34a28b30eb9b3bab6b1b6a8112eb1c427c67

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