script: Move gamepad DOM interfaces to script/dom/gamepad/ (#38900)

Moves interfaces defined by the gamepad spec to the
`script/dom/gamepad/` module from `script/dom/`.

Testing: Just a refactor shouldn't need any testing
Fixes: N/A

Signed-off-by: Ashwin Naren <arihant2math@gmail.com>

components/script/dom/gamepad/gamepadevent.rs

@@ -0,0 +1,118 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
+
+use dom_struct::dom_struct;
+use js::rust::HandleObject;
+use stylo_atoms::Atom;
+
+use super::gamepad::Gamepad;
+use crate::dom::bindings::codegen::Bindings::EventBinding::Event_Binding::EventMethods;
+use crate::dom::bindings::codegen::Bindings::GamepadEventBinding;
+use crate::dom::bindings::codegen::Bindings::GamepadEventBinding::GamepadEventMethods;
+use crate::dom::bindings::error::Fallible;
+use crate::dom::bindings::inheritance::Castable;
+use crate::dom::bindings::reflector::reflect_dom_object_with_proto;
+use crate::dom::bindings::root::{Dom, DomRoot};
+use crate::dom::bindings::str::DOMString;
+use crate::dom::event::Event;
+use crate::dom::window::Window;
+use crate::script_runtime::CanGc;
+
+#[dom_struct]
+pub(crate) struct GamepadEvent {
+    event: Event,
+    gamepad: Dom<Gamepad>,
+}
+
+pub(crate) enum GamepadEventType {
+    Connected,
+    Disconnected,
+}
+
+impl GamepadEvent {
+    fn new_inherited(gamepad: &Gamepad) -> GamepadEvent {
+        GamepadEvent {
+            event: Event::new_inherited(),
+            gamepad: Dom::from_ref(gamepad),
+        }
+    }
+
+    pub(crate) fn new(
+        window: &Window,
+        type_: Atom,
+        bubbles: bool,
+        cancelable: bool,
+        gamepad: &Gamepad,
+        can_gc: CanGc,
+    ) -> DomRoot<GamepadEvent> {
+        Self::new_with_proto(window, None, type_, bubbles, cancelable, gamepad, can_gc)
+    }
+
+    fn new_with_proto(
+        window: &Window,
+        proto: Option<HandleObject>,
+        type_: Atom,
+        bubbles: bool,
+        cancelable: bool,
+        gamepad: &Gamepad,
+        can_gc: CanGc,
+    ) -> DomRoot<GamepadEvent> {
+        let ev = reflect_dom_object_with_proto(
+            Box::new(GamepadEvent::new_inherited(gamepad)),
+            window,
+            proto,
+            can_gc,
+        );
+        {
+            let event = ev.upcast::<Event>();
+            event.init_event(type_, bubbles, cancelable);
+        }
+        ev
+    }
+
+    pub(crate) fn new_with_type(
+        window: &Window,
+        event_type: GamepadEventType,
+        gamepad: &Gamepad,
+        can_gc: CanGc,
+    ) -> DomRoot<GamepadEvent> {
+        let name = match event_type {
+            GamepadEventType::Connected => "gamepadconnected",
+            GamepadEventType::Disconnected => "gamepaddisconnected",
+        };
+
+        GamepadEvent::new(window, name.into(), false, false, gamepad, can_gc)
+    }
+}
+
+impl GamepadEventMethods<crate::DomTypeHolder> for GamepadEvent {
+    // https://w3c.github.io/gamepad/#gamepadevent-interface
+    fn Constructor(
+        window: &Window,
+        proto: Option<HandleObject>,
+        can_gc: CanGc,
+        type_: DOMString,
+        init: &GamepadEventBinding::GamepadEventInit,
+    ) -> Fallible<DomRoot<GamepadEvent>> {
+        Ok(GamepadEvent::new_with_proto(
+            window,
+            proto,
+            Atom::from(type_),
+            init.parent.bubbles,
+            init.parent.cancelable,
+            &init.gamepad,
+            can_gc,
+        ))
+    }
+
+    // https://w3c.github.io/gamepad/#gamepadevent-interface
+    fn Gamepad(&self) -> DomRoot<Gamepad> {
+        DomRoot::from_ref(&*self.gamepad)
+    }
+
+    // https://dom.spec.whatwg.org/#dom-event-istrusted
+    fn IsTrusted(&self) -> bool {
+        self.event.IsTrusted()
+    }
+}