Initial implementation of GPUDevice for WebGPU

Added the WebIDL bindigs for GPUDevice, GPUObjectDescriptorBase, GPUDeviceDescriptor, GPUObjectBase
Implemented the `requestDevice` function of `GPUAdapter`

components/script/dom/gpudevice.rs

@@ -0,0 +1,91 @@
+/* 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 crate::dom::bindings::cell::DomRefCell;
+use crate::dom::bindings::codegen::Bindings::GPUDeviceBinding::{self, GPUDeviceMethods};
+use crate::dom::bindings::reflector::reflect_dom_object;
+use crate::dom::bindings::root::{Dom, DomRoot};
+use crate::dom::bindings::str::DOMString;
+use crate::dom::eventtarget::EventTarget;
+use crate::dom::globalscope::GlobalScope;
+use crate::dom::gpuadapter::GPUAdapter;
+use crate::script_runtime::JSContext as SafeJSContext;
+use dom_struct::dom_struct;
+use js::jsapi::{Heap, JSObject};
+use std::ptr::NonNull;
+use webgpu::WebGPUDevice;
+
+#[dom_struct]
+pub struct GPUDevice {
+    eventtarget: EventTarget,
+    adapter: Dom<GPUAdapter>,
+    #[ignore_malloc_size_of = "mozjs"]
+    extensions: Heap<*mut JSObject>,
+    #[ignore_malloc_size_of = "mozjs"]
+    limits: Heap<*mut JSObject>,
+    label: DomRefCell<Option<DOMString>>,
+    device: WebGPUDevice,
+}
+
+impl GPUDevice {
+    fn new_inherited(
+        adapter: &GPUAdapter,
+        extensions: Heap<*mut JSObject>,
+        limits: Heap<*mut JSObject>,
+        device: WebGPUDevice,
+    ) -> GPUDevice {
+        Self {
+            eventtarget: EventTarget::new_inherited(),
+            adapter: Dom::from_ref(adapter),
+            extensions,
+            limits,
+            label: DomRefCell::new(None),
+            device,
+        }
+    }
+
+    #[allow(unsafe_code)]
+    pub fn new(
+        global: &GlobalScope,
+        adapter: &GPUAdapter,
+        extensions: Heap<*mut JSObject>,
+        limits: Heap<*mut JSObject>,
+        device: WebGPUDevice,
+    ) -> DomRoot<GPUDevice> {
+        reflect_dom_object(
+            Box::new(GPUDevice::new_inherited(
+                adapter, extensions, limits, device,
+            )),
+            global,
+            GPUDeviceBinding::Wrap,
+        )
+    }
+}
+
+impl GPUDeviceMethods for GPUDevice {
+    /// https://gpuweb.github.io/gpuweb/#dom-gpudevice-adapter
+    fn Adapter(&self) -> DomRoot<GPUAdapter> {
+        DomRoot::from_ref(&self.adapter)
+    }
+
+    /// https://gpuweb.github.io/gpuweb/#dom-gpudevice-extensions
+    fn Extensions(&self, _cx: SafeJSContext) -> NonNull<JSObject> {
+        NonNull::new(self.extensions.get()).unwrap()
+    }
+
+    /// https://gpuweb.github.io/gpuweb/#dom-gpudevice-limits
+    fn Limits(&self, _cx: SafeJSContext) -> NonNull<JSObject> {
+        NonNull::new(self.extensions.get()).unwrap()
+    }
+
+    /// https://gpuweb.github.io/gpuweb/#dom-gpuobjectbase-label
+    fn GetLabel(&self) -> Option<DOMString> {
+        self.label.borrow().clone()
+    }
+
+    /// https://gpuweb.github.io/gpuweb/#dom-gpuobjectbase-label
+    fn SetLabel(&self, value: Option<DOMString>) {
+        *self.label.borrow_mut() = value;
+    }
+}