When removing, check existing object instead of given one
When removing, check existing object instead of given one

This is to avoid people manipulating an object's properties before
removing it in such a way that they could pass the authorization check
with the modified properties but wouldn't have been able to pass it had
they not modified those properties.

foam-framework/foam2,foam-framework/foam2,foam-framework/foam2,jacksonic/vjlofvhjfgm,foam-framework/foam2,jacksonic/vjlofvhjfgm,foam-framework/foam2,jacksonic/vjlofvhjfgm