text: // Based on similar tests in html/infrastructure/safe-passing-of-structured-data/shared-array-buffers/.
  "use strict";
  self.importScripts("/resources/testharness.js");
  
  let state = "start in worker";
  
  self.onmessage = e => {
    if (e.data === "start in window") {
      assert_equals(state, "start in worker");
      e.source.postMessage(state);
      state = "we are expecting a messageerror due to the window sending us an RTCEncodedVideoFrame or RTCEncodedAudioFrame";
    } else {
      e.source.postMessage(`worker onmessage was reached when in state "${state}" and data ${e.data}`);
    }
  };
  
  self.onmessageerror = e => {
    if (state === "we are expecting a messageerror due to the window sending us an RTCEncodedVideoFrame or RTCEncodedAudioFrame") {
      assert_equals(e.constructor.name, "ExtendableMessageEvent", "type");
      assert_equals(e.data, null, "data");
      assert_equals(e.origin, self.origin, "origin");
      assert_not_equals(e.source, null, "source");
      assert_equals(e.ports.length, 0, "ports length");
  
      state = "onmessageerror was received in worker";
      e.source.postMessage(state);
    } else {
      e.source.postMessage(`worker onmessageerror was reached when in state "${state}" and data ${e.data}`);
    }
  };
  