reassemble method

void reassemble (Element root)

Cause the entire subtree rooted at the given Element to be entirely rebuilt. This is used by development tools when the application code has changed and is being hot-reloaded, to cause the widget tree to pick up any changed implementations.

This is expensive and should not be called except during development.

Implementation 

void reassemble(Element root) {
  Timeline.startSync('Dirty Element Tree');
  try {
    assert(root._parent == null);
    assert(root.owner == this);
    root._reassemble();
  } finally {
    Timeline.finishSync();
  }
}