Add a persistent DOM event listener promise.

dream/platform/src2/dream/mixin_promise.js

 /*global RSVP, FileReader */
+/*jslint unparam: true */
 (function (window, RSVP, FileReader) {
   "use strict";
 
+  window.loopEventListener = function (target, type, useCapture, callback) {
+    //////////////////////////
+    // Infinite event listener (promise is never resolved)
+    // eventListener is removed when promise is cancelled/rejected
+    //////////////////////////
+    var handle_event_callback,
+      callback_promise;
+
+    function cancelResolver() {
+      if ((callback_promise !== undefined) &&
+          (typeof callback_promise.cancel === "function")) {
+        callback_promise.cancel();
+      }
+    }
+
+    function canceller() {
+      if (handle_event_callback !== undefined) {
+        target.removeEventListener(type, handle_event_callback, useCapture);
+      }
+      cancelResolver();
+    }
+    function itsANonResolvableTrap(resolve, reject) {
+
+      handle_event_callback = function (evt) {
+        evt.stopPropagation();
+        evt.preventDefault();
+        cancelResolver();
+        callback_promise = new RSVP.Queue()
+          .push(function () {
+            return callback(evt);
+          })
+          .push(undefined, function (error) {
+            if (!(error instanceof RSVP.CancellationError)) {
+              canceller();
+              reject(error);
+            }
+          });
+      };
+
+      target.addEventListener(type, handle_event_callback, useCapture);
+    }
+    return new RSVP.Promise(itsANonResolvableTrap, canceller);
+  };
+
   window.promiseEventListener = function (target, type, useCapture) {
     //////////////////////////
     // Resolve the promise as soon as the event is triggered