fix a11y crash seen on moving chart wizard dialog
fix a11y crash seen on moving chart wizard dialog

Change-Id: Ic3ba292e28fe12d7dcc2c2e67aeea48a4c8aaac2

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