This is needed to prevent memory leaks. The DOM
listeners don’t need to be removed for simple examples,
but a big internal app shows memory leaks because of them.
BREAKING CHANGE:
- `Renderer.listen` now has to return a function that
removes the event listener.
BREAKING CHANGE:
- Platform pipes can only contain types and arrays of types,
but no bindings any more.
- When using transformers, platform pipes need to be specified explicitly
in the pubspec.yaml via the new config option
`platform_pipes`.
- `Compiler.compileInHost` now returns a `HostViewFactoryRef`
- Component view is not yet created when component constructor is called.
-> use `onInit` lifecycle callback to access the view of a component
- `ViewRef#setLocal` has been moved to new type `EmbeddedViewRef`
- `internalView` is gone, use `EmbeddedViewRef.rootNodes` to access
the root nodes of an embedded view
- `renderer.setElementProperty`, `..setElementStyle`, `..setElementAttribute` now
take a native element instead of an ElementRef
- `Renderer` interface now operates on plain native nodes,
instead of `RenderElementRef`s or `RenderViewRef`s
Closes#5993
