Base class for Angular Views, provides change detection functionality.
A change-detection tree collects all views that are to be checked for changes.
Use the methods to add and remove views from the tree, initiate change-detection,
and explicitly mark views as _dirty_, meaning that they have changed and need to be rerendered.
Detaches this view from the change-detection tree. A detached view is not checked until it is reattached. Use in combination with `detectChanges()` to implement local change detection checks.Detached views are not checked during change detection runs until they are re-attached, even if they are marked as dirty.
When a view uses the `OnPush` (checkOnce) change detection strategy, explicitly marks the view as changed so that it can be checked again.Components are normally marked as dirty (in need of rerendering) when inputs have changed or events have fired in the view. Call this method to ensure that a component is checked even if these triggers have not occured.