Code clean up, and better comments, along with z-index fixes for scrollbar and avatar menu

src/components/structures/RoomSubList.js

@@ -119,7 +119,6 @@ var RoomSubList = React.createClass({
     // The dataset elements are added in the RoomList _initAndPositionStickyHeaders method
     isCollapsableOnClick: function() {
         var stuck = this.refs.header.dataset.stuck;
-        var topBottomSticky = this.refs.header.dataset.topBottomSticky;
         if (this.state.hidden || stuck === undefined || stuck === "none") {
             return true;
         } else {
@@ -249,11 +248,8 @@ var RoomSubList = React.createClass({
 
     roomNotificationCount: function() {
         var self = this;
-        var subListCount = 0;
-        var subListHighlight = false;
-        var cli = MatrixClientPeg.get();
 
-        this.props.list.map(function(room) {
+        return this.props.list.reduce(function(result, room) {
             var roomNotifState = RoomNotifs.getRoomNotifsState(room.roomId);
             var highlight = room.getUnreadNotificationCount('highlight') > 0 || self.props.label === 'Invites';
             var notificationCount = room.getUnreadNotificationCount();
@@ -263,14 +259,13 @@ var RoomSubList = React.createClass({
             const badges = notifBadges || mentionBadges;
 
             if (badges) {
-                subListCount += notificationCount;
+                result[0] += notificationCount;
                 if (highlight) {
-                    subListHighlight = true;
+                    result[1] = true;
                 }
             }
-        });
-
-        return [subListCount, subListHighlight];
+            return result;
+        }, [0, false]);
     },
 
     _updateSubListCount: function() {

src/skins/vector/css/matrix-react-sdk/views/rooms/RoomList.css

@@ -35,5 +35,5 @@ limitations under the License.
 
 /* Make sure the scrollbar is above the sticky headers from RoomList */
 .mx_RoomList_scrollbar .gm-scrollbar.-vertical {
-    z-index: 3;
+    z-index: 5;
 }

src/skins/vector/css/vector-web/structures/LeftPanel.css

@@ -49,6 +49,7 @@ limitations under the License.
     flex: 1 1 0;
 
     overflow-y: auto;
+    z-index: 5;
 }
 
 .mx_LeftPanel.collapsed .mx_BottomLeftMenu {

src/skins/vector/css/vector-web/structures/RoomSubList.css

@@ -46,7 +46,7 @@ limitations under the License.
 .mx_RoomSubList_label.mx_RoomSubList_fixed {
     position: fixed;
     top: 0;
-    z-index: 2;
+    z-index: 4;
     /* pointer-events: none; */
 }