add hasAssociation helper

src/models/event.js

@@ -921,6 +921,15 @@ utils.extend(module.exports.MatrixEvent.prototype, {
         }
     },
 
+    /**
+     * Checks if this event is associated with another event. See `getAssociatedId`.
+     *
+     * @return {bool}
+     */
+    hasAssocation() {
+        return !!this.getAssociatedId();
+    },
+
     /**
      * Update the related id with a new one.
      *

src/scheduler.js

@@ -178,7 +178,7 @@ MatrixScheduler.RETRY_BACKOFF_RATELIMIT = function(event, attempts, err) {
  */
 MatrixScheduler.QUEUE_MESSAGES = function(event) {
     // enqueue messages or events that associate with another event (redactions and relations)
-    if (event.getType() === "m.room.message" || !!event.getAssociatedId()) {
+    if (event.getType() === "m.room.message" || event.hasAssocation()) {
         // put these events in the 'message' queue.
         return "message";
     }