bring back old behaviour to also show member avatars if not marked as 1:1 room

src/components/views/avatars/RoomAvatar.js

@@ -108,16 +108,29 @@ module.exports = React.createClass({
     },
 
     getOneToOneAvatar: function(props) {
-        if (!props.room) return null;
+        const room = props.room;
+        if (!room) {
+            return null;
+        }
+        let otherMember = null;
+        const otherUserId = DMRoomMap.shared().getUserIdForRoomId(room.roomId);
+        if (otherUserId) {
+            otherMember = room.getMember(otherUserId);
+        } else {
+            // if the room is not marked as a 1:1, but only has max 2 members
+            // then still try to show any avatar (pref. other member)
+            const totalMemberCount = room.getJoinedMemberCount() +
+                room.getInvitedMemberCount();
+            const members = room.currentState.getMembers();
+            if (totalMemberCount == 2) {
+                const myUserId = MatrixClientPeg.get().getUserId();
+                otherMember = members.find(m => m.userId !== myUserId);
+            } else if(totalMemberCount == 1) {
+                otherMember = members[0];
+            }
 
-        const otherUserId = DMRoomMap.shared().getUserIdForRoomId(props.room.roomId);
-        if (!otherUserId) {
-            return null;
-        }
-        const otherMember = props.room.getMember(otherUserId);
-        if (!otherMember) {
-            return null;
         }
+        if (otherMember) {
             return otherMember.getAvatarUrl(
                 MatrixClientPeg.get().getHomeserverUrl(),
                 Math.floor(props.width * window.devicePixelRatio),
@@ -125,6 +138,8 @@ module.exports = React.createClass({
                 props.resizeMethod,
                 false,
             );
+        }
+        return null;
     },
 
     onRoomAvatarClick: function() {