small cleanup of SystemWindow
small cleanup of SystemWindow

Change-Id: I4bced5e8d97cd72a75c7d62e5ad0bfee9eb60097

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