[Telepathy] stream engine is not a channel handler

[Robert McQueen]

Raphael Slinckx wrote:
>   * stream-engine (you need darcs version because you need the .chandler
> file installed in ~/.telepathy or /usr/share/telepathy/managers/ any
> other prefix is *not* going to work)

Hmm, I don't really consider the stream-engine as a channel handler,
because it doesn't make sense to launch more than one handler for one
channel type in general. If you have two chat UIs or two call UIs,
launching all of the handlers for a given channel type is totally wrong
- the user (or MC's, or the desktop) policy should dictate which one to
launch. I don't see that MC should have to treat streamed media channels
any differently.

We need to revert this and choose an alternative strategy:
 * special-case MC to launch it, which is what the 770 does (blurgh)
 * come up with some mad way of .chandler files having dependencies and
filtering and stuff (eww)
 * just have the voip UI take responsibility for launching the engine
(kinda the most correct - a UI could use farsight or something else
directly, you're not obliged to use our stream engine, so this
represents the real dependency of our handler on the stream engine)
 * make some way of .chandler files listing multiple services to
activate (possibly a reasonable compromise)

Comments?

Regards,
Rob