get rid of obsolete showEmpty prop

src/components/structures/RoomSubList.js

@@ -56,7 +56,6 @@ const RoomSubList = React.createClass({
         emptyContent: PropTypes.node, // content shown if the list is empty
         headerItems: PropTypes.node, // content shown in the sublist header
         extraTiles: PropTypes.arrayOf(PropTypes.node), // extra elements added beneath tiles
-        showEmpty: PropTypes.bool,
     },
 
     getInitialState: function() {
@@ -72,7 +71,6 @@ const RoomSubList = React.createClass({
             }, // NOP
             extraTiles: [],
             isInvite: false,
-            showEmpty: true,
         };
     },
 

src/components/views/rooms/RoomList.js

@@ -508,7 +508,6 @@ module.exports = React.createClass({
             const defaultProps = {
                 collapsed: self.props.collapsed,
                 searchFilter: self.props.searchFilter,
-                showEmpty: showEmpty,
                 incomingCall: self.state.incomingCall,
             };
             return subListsProps.reduce((components, props, i) => {