trivial to add more properties
finished first cut at SetTextProperty. This triggers lots of crashes in
range/selection code where we're holding onto a stale frame pointer (at
least, that's my best guess.)
synched with Charlie's change-o-rama
added an assert in DeleteTextTxn::Init() checking aNumCharsToDelete vs.
0
NS_ASSERTION(0!=aNumCharsToDelete, "bad arg, numCharsToDelete");
if the number of chars to delete is 0, we shouldn't be creating a
transaction at all. I had never seen this condition arise before
Charlie's checkin, I don't know if he introduced it or if it was a
latent bug I just never tripped over before.