api: overhaul pointer API

- Rename `CursorMoved` to `PointerMoved`.
- Rename `CursorEntered` to `PointerEntered`.
- Rename `CursorLeft` to `PointerLeft`.
- Rename `MouseInput` to `PointerButton`.
- Add `position` to every `PointerEvent`.
- Remove `Touch`, which is folded into the `Pointer*` events.
- New `PointerType` added to `PointerEntered` and `PointerLeft`,
  signifying which pointer type is the source of this event.
- New `PointerSource` added to `PointerMoved`, similar to `PointerType`
  but holding additional data.
- New `ButtonSource` added to `PointerButton`, similar to `PointerType`
  but holding pointer type specific buttons. Use
  `ButtonSource::mouse_button()` to easily normalize any pointer button
  type to a generic mouse button.
- In the same spirit rename `DeviceEvent::MouseMotion` to `PointerMotion`.
- Remove `Force::Calibrated::altitude_angle`.

Fixes #3833.
Fixes #883.
Fixes #336.

Co-authored-by: Kirill Chibisov <contact@kchibisov.com>

src/platform_impl/web/web_sys/mod.rs

@@ -18,7 +18,6 @@ use wasm_bindgen::JsCast;
 use web_sys::{Document, HtmlCanvasElement, Navigator, PageTransitionEvent, VisibilityState};
 
 pub use self::canvas::{Canvas, Style};
-pub use self::event::ButtonsState;
 pub use self::event_handle::EventListenerHandle;
 pub use self::resize_scaling::ResizeScaleHandle;
 pub use self::schedule::Schedule;