script: Move WebRTC DOM interfaces to script/dom/webrtc/ (#39023)

Move interfaces defined by the WebRTC specification to the
`script/dom/webrtc/` module from `script/dom/`.

`script/dom/rtc*.rs -> script/dom/webrtc/`

Testing: No changes, just a refactoring

Fixes (partially): #38901

Signed-off-by: Andrei Volykhin <volykhin.andrei@huawei.com>
Co-authored-by: Andrei Volykhin <volykhin.andrei@huawei.com>

components/script/dom/webrtc/rtcdatachannelevent.rs

@@ -0,0 +1,99 @@
+/* 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 crate::dom::bindings::codegen::Bindings::EventBinding::EventMethods;
+use crate::dom::bindings::codegen::Bindings::RTCDataChannelEventBinding::{
+    RTCDataChannelEventInit, RTCDataChannelEventMethods,
+};
+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::rtcdatachannel::RTCDataChannel;
+use crate::dom::window::Window;
+use crate::script_runtime::CanGc;
+
+#[dom_struct]
+pub(crate) struct RTCDataChannelEvent {
+    event: Event,
+    channel: Dom<RTCDataChannel>,
+}
+
+impl RTCDataChannelEvent {
+    fn new_inherited(channel: &RTCDataChannel) -> RTCDataChannelEvent {
+        RTCDataChannelEvent {
+            event: Event::new_inherited(),
+            channel: Dom::from_ref(channel),
+        }
+    }
+
+    pub(crate) fn new(
+        window: &Window,
+        type_: Atom,
+        bubbles: bool,
+        cancelable: bool,
+        channel: &RTCDataChannel,
+        can_gc: CanGc,
+    ) -> DomRoot<RTCDataChannelEvent> {
+        Self::new_with_proto(window, None, type_, bubbles, cancelable, channel, can_gc)
+    }
+
+    fn new_with_proto(
+        window: &Window,
+        proto: Option<HandleObject>,
+        type_: Atom,
+        bubbles: bool,
+        cancelable: bool,
+        channel: &RTCDataChannel,
+        can_gc: CanGc,
+    ) -> DomRoot<RTCDataChannelEvent> {
+        let event = reflect_dom_object_with_proto(
+            Box::new(RTCDataChannelEvent::new_inherited(channel)),
+            window,
+            proto,
+            can_gc,
+        );
+        {
+            let event = event.upcast::<Event>();
+            event.init_event(type_, bubbles, cancelable);
+        }
+        event
+    }
+}
+
+impl RTCDataChannelEventMethods<crate::DomTypeHolder> for RTCDataChannelEvent {
+    // https://www.w3.org/TR/webrtc/#dom-rtcdatachannelevent-constructor
+    fn Constructor(
+        window: &Window,
+        proto: Option<HandleObject>,
+        can_gc: CanGc,
+        type_: DOMString,
+        init: &RTCDataChannelEventInit,
+    ) -> DomRoot<RTCDataChannelEvent> {
+        RTCDataChannelEvent::new_with_proto(
+            window,
+            proto,
+            Atom::from(type_),
+            init.parent.bubbles,
+            init.parent.cancelable,
+            &init.channel,
+            can_gc,
+        )
+    }
+
+    // https://www.w3.org/TR/webrtc/#dom-datachannelevent-channel
+    fn Channel(&self) -> DomRoot<RTCDataChannel> {
+        DomRoot::from_ref(&*self.channel)
+    }
+
+    // https://dom.spec.whatwg.org/#dom-event-istrusted
+    fn IsTrusted(&self) -> bool {
+        self.event.IsTrusted()
+    }
+}