BREAKING CHANGE:
- all `…Metadata` classes have been removed. Use the corresponding decorator
as constructor or for `instanceof` checks instead.
- Example:
* Before: `new ComponentMetadata(…)`
* After: `new Component(…)`
- Note: `new Component(…)` worked before as well.
Closes#9729
BREAKING CHANGE:
`Type` is now `Type<T>` which means that in most cases you have to
use `Type<any>` in place of `Type`.
We don't expect that any user applications use the `Type` type.