fdo#58242: getCrsrPropertyValue: fix crashes when PaM not on SwTxtNode
fdo#58242: getCrsrPropertyValue: fix crashes when PaM not on SwTxtNode

Change-Id: I67042b5d689457921a928454c9051f0402be17e6

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