message: Get tests passing in Edge.
  Edge's ErrorEvent#message is different than ErrorEvent#error.message. It just complains that an uncaught error was thrown.
diff: @@ -99,7 +99,8 @@ suite('static dependencies', () => {
  // We only expect this error once.
  window.uncaughtErrorFilter = undefined;
  // Only filter a failure to fetch a file that does not exist.
  - return /Failed to fetch .*static\/y\/not-found\.js/.test(e.message);
  + return /Failed to fetch .*static\/y\/not-found\.js/.test(
  + e.error.message);
  };
  define(['./not-found.js'], () => assert.fail());
  @@ -219,7 +220,8 @@ suite('top-level modules', () => {
  // We only expect this error once.
  window.uncaughtErrorFilter = undefined;
  // Look for a failure to fetch the file that does not exist.
  - return /Failed to fetch .*static\/y\/not-found\.js/.test(e.message);
  + return /Failed to fetch .*static\/y\/not-found\.js/.test(
  + e.error.message);
  };
  // We order top-level modules by injecting dependencies between them.
  // However, unlike normal dependencies, if module 1 fails, we should still
  