zone-patch-timeout.ts

// Save the original reference to setTimeout
const originalSetTimeout = window.setTimeout;
// Overwrite the API with a function which wraps callback in zone
window.setTimeout = function(callback, delay) {
  // Invoke the original API but wrap the callback in zone
  return originalSetTimeout(
    // Wrap the callback method
    Zone.current.wrap(callback),
    delay
  );
}