Fix ooo51302-1.ods: check for special index value of -1
Fix ooo51302-1.ods: check for special index value of -1

Change-Id: I3fbb700300d18a878cbf23c94e35bc69f864824b

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