More PR feedback

src/components/structures/RoomView.js

@@ -117,6 +117,7 @@ module.exports = React.createClass({
             guestsCanJoin: false,
             canPeek: false,
 
+            // error object, as from the matrix client/server API
             // If we failed to load information about the room,
             // store the error here.
             roomLoadError: null,

src/components/views/rooms/RoomPreviewBar.js

@@ -43,6 +43,8 @@ module.exports = React.createClass({
         room: React.PropTypes.object,
 
         // The alias that was used to access this room, if appropriate
+        // If given, this will be how the room is referred to (eg.
+        // in error messages).
         roomAlias: React.PropTypes.object,
     },