feat(external-api) Forward CONFERENCE_CREATED_TIMESTAMP to iframe

modules/API/API.js

@@ -2138,6 +2138,21 @@ class API {
     }
 
 
+    /**
+     * Notify external application (if API is enabled) the conference
+     * start time.
+     *
+     * @param {number} timestamp - Timestamp conference was created.
+     * @returns {void}
+     */
+    notifyConferenceCreatedTimestamp(timestamp) {
+        this._sendEvent({
+            name: 'conference-created-timestamp',
+            timestamp
+        });
+    }
+
+
     /**
      * Notify the external application (if API is enabled) if the connection type changed.
      *