Defines BaseChannelRolesInterface, needed to set different roles for the group members.
This interface can be plugged to channels
Here is the final specification:

org.freedesktop.Telepathy.Channel.Interface.Roles

Methods:
UpdateRoles             (a{uu}:ContactRoles)    -> nothing

Signals:
RolesChanged (a{uu}:Added, a{uu}:Removed)

Properties:
Roles           a{uu} (Handle_Roles_Map)        Read only
CanUpdateRoles  b                               Read only

Types:
Channel_Roles           Flags   u
Handle_Roles_Map        Mapping a{uu}

.

Approved by Tiago Salem Herrmann, system-apps-ci-bot.