fdo#46340: fix crash in SdrGrafObj::getInputStream:
fdo#46340: fix crash in SdrGrafObj::getInputStream:

Add the ridiculous hack that used to be here (and distributed across
various GetDocumentStream methods to make it non-obvious)
that makes this not crash by accident.

(regression from fd95f1ab6220c6a530fd2e4e727417f504a5db51)

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