Voice rooms prototype (#8084)

* Add voice room labs flag

Signed-off-by: Robin Townsend <robin@robin.town>

* Add more widget actions for interacting with Jitsi

Signed-off-by: Robin Townsend <robin@robin.town>

* Factor out a more generic Jitsi creation utility

Signed-off-by: Robin Townsend <robin@robin.town>

* Add utilities for managing voice channels

Signed-off-by: Robin Townsend <robin@robin.town>

* Enable creation of voice rooms

Signed-off-by: Robin Townsend <robin@robin.town>

* Force a maximized view of voice channel widgets

Signed-off-by: Robin Townsend <robin@robin.town>

* Add voice channel store

Signed-off-by: Robin Townsend <robin@robin.town>

* Factor out a more generic FacePile

Signed-off-by: Robin Townsend <robin@robin.town>

* Implement room tile changes for voice rooms

Signed-off-by: Robin Townsend <robin@robin.town>

* Add interactive radio component to the left panel

Signed-off-by: Robin Townsend <robin@robin.town>

* Test voice rooms

Signed-off-by: Robin Townsend <robin@robin.town>

* Update name of call room type

Signed-off-by: Robin Townsend <robin@robin.town>

* Clarify that voice rooms are under development

Signed-off-by: Robin Townsend <robin@robin.town>

* Use readonly

Signed-off-by: Robin Townsend <robin@robin.town>

* Move acks to the end of handlers

Signed-off-by: Robin Townsend <robin@robin.town>

* Add comment about avatar URLs coming from Jitsi

Signed-off-by: Robin Townsend <robin@robin.town>

* Don't use unicode ellipses

for translation reasons?

Signed-off-by: Robin Townsend <robin@robin.town>

* Fix tests

Signed-off-by: Robin Townsend <robin@robin.town>

* Fix tests, again

Signed-off-by: Robin Townsend <robin@robin.town>

* Remove unnecessary export

Signed-off-by: Robin Townsend <robin@robin.town>

* Ack Jitsi events when we wait for them

Signed-off-by: Robin Townsend <robin@robin.town>

res/css/views/elements/_FacePile.scss

@@ -20,7 +20,7 @@ limitations under the License.
         flex-direction: row-reverse;
         vertical-align: middle;
 
-        > .mx_FacePile_face + .mx_FacePile_face {
+        > * + * {
             margin-right: -8px;
         }