Make last seen indicator more stable, with less forced removal

FREEBIE

js/views/conversation_view.js

@@ -278,14 +278,14 @@
             options = options || {};
             _.defaults(options, {scroll: true});
 
-            this.removeLastSeenIndicator({force: true});
-
             var oldestUnread = this.model.messageCollection.find(function(model) {
                 return model.get('unread');
             });
             var unreadCount = this.model.get('unreadCount');
 
             if (oldestUnread && unreadCount > 0) {
+                this.removeLastSeenIndicator({force: true});
+
                 this.lastSeenIndicator = new Whisper.LastSeenIndicatorView({count: unreadCount});
                 var unreadEl = this.lastSeenIndicator.render().$el;
 
@@ -303,6 +303,9 @@
                     }
                 }.bind(this), 1);
             }
+            else {
+                this.removeLastSeenIndicator({force: false});
+            }
         },
 
         focusMessageField: function() {