* Addresses #2287439 incompletely
* The most likely reason for a reply/forward to get stuck in the Outbox
is that the referenced message has been deleted from the client, with
the deletion occuring BEFORE the message gets sent (currently, the two
are completely independent)
* This change causes deletes NOT to be sent to the server if the message
to be deleted is referenced by an outgoing message
Change-Id: I146f63ab345c07e684790e1d7d1fc08870468bbf
