[ci no changelog needed]
[Task link](https://www.pivotaltracker.com/story/show/181413200)
This PR implements content clipping for the ScrollArea component.
List of changes:
- Implemented `InstanceWithAttachedLayer` abstraction that allows creating additional sublayers for our components. In the future, this abstraction can be used for text rendering as well (right now text rendering requires additional hardcoded layers).
- Fixed `complex-shape-system` demo scene by fixing `node_searcher_mask` layer.
- Fixed `SublayersModel::remove` - it was not clearing the `layer_placement` hashmap.
- Implemented disabling the wheel scrolling in `Navigator`, and refactored it to reduce the number of functions arguments by introducing a `NavigatorSettings` struct.
Video (`scroll_area` demo):
https://user-images.githubusercontent.com/6566674/164506455-e177a7a7-9f1c-4f50-888f-112423cebbe4.mp4
# Important Notes
- `InstanceWithAttachedLayer` is implemented in such a way that it allows an extension in the future - namely to use it to simplify text rendering. The implementation might be simplified though.
