fixes #3847

JingleRTPConnection shuts down the WebRTCWrapper before transitioning into a terminal state.
(This allows us to make sure it is actually closed when reaching that state);
However that means that, when we get a UI redrawn inbetween closing and transitioning we might
still be in SESSION_ACCEPTED but with no PeerConnection. This traditionally has triggered
an IllegalStateException on getting the EndUserState.
This commit catches the ISE and returns 'ENDING' instead.
Chances are that this is only visibiliy for a very brief time in the UI before the transition
triggers the UI to redraw with the proper state.

fixes #3848

Currently Conversations lacks any keyboard shortcut to send a message if enter_is_send is disabled.

KeyboardListener has been extended to include the original KeyEvent as an argument.

fixes #3829

camea -> camera

some implementations will transform the following SDP coming from Firefox

m=audio 12346 RTP/AVP 101
a=rtpmap:101 telephone-event/8000
a=fmtp:101 0-15

to

<payload-type channels="1" name="telephone-event" clockrate="8000" id="101">
  <parameter value="0-15" xmlns="urn:xmpp:jingle:apps:rtp:1"/>
</payload-type>

While a missing name attribute is not legal according to the XEP; and 0-15 are
technically not just one value the following commit will accept it if there is
just one paramater.

on some phones the onBackendConnected finishes prior to the onActivityResult()
leading to the pending photo uri being cleared before processing the result.

this leads to 'Take photo' not working.

but we probably don’t need to clear the photo uri if there is to activiyResult
to clear as well