Auto merge of #24708 - szeged:webgpu-base, r=gterzian,kvark

Initial implementation of WebGPU API

<!-- Please describe your changes on the following line: -->
- Added the WebIDL bindings for GPU and GPUadapter interfaces.
- Created a background thread for WebGPU api calls.
- Established the async communication between the background thread and the WebGPU interfaces.
- Implemented the `requesAdapter` function of `navigator.gpu`

`./mach test-tidy` reports an error due to the different `arrayvec` version used in `servo` and `webgpu`, so added it to the ignore list in `servo-tidy.toml`

---
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- [x] `./mach build -d` does not report any errors
- [ ] `./mach test-tidy` does not report any errors
- [ ] These changes addresses a part of #https://github.com/servo/servo/issues/24706

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cc @jdm, cc @kvark

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1 files changed, 63 insertions, 0 deletions

diff --git a/components/script/dom/gpuadapter.rs b/components/script/dom/gpuadapter.rs
new file mode 100644
index 00000000000..ec970439e8a
--- /dev/null
+++ b/components/script/dom/gpuadapter.rs
@@ -0,0 +1,63 @@
+/* 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::codegen::Bindings::GPUAdapterBinding::{self, GPUAdapterMethods};
+use crate::dom::bindings::reflector::{reflect_dom_object, Reflector};
+use crate::dom::bindings::root::DomRoot;
+use crate::dom::bindings::str::DOMString;
+use crate::dom::globalscope::GlobalScope;
+use crate::script_runtime::JSContext as SafeJSContext;
+use dom_struct::dom_struct;
+use js::jsapi::{Heap, JSObject};
+use std::ptr::NonNull;
+use webgpu::WebGPUAdapter;
+
+#[dom_struct]
+pub struct GPUAdapter {
+    reflector_: Reflector,
+    name: DOMString,
+    #[ignore_malloc_size_of = "mozjs"]
+    extensions: Heap<*mut JSObject>,
+    adapter: WebGPUAdapter,
+}
+
+impl GPUAdapter {
+    pub fn new_inherited(
+        name: DOMString,
+        extensions: Heap<*mut JSObject>,
+        adapter: WebGPUAdapter,
+    ) -> GPUAdapter {
+        GPUAdapter {
+            reflector_: Reflector::new(),
+            name,
+            extensions,
+            adapter,
+        }
+    }
+
+    pub fn new(
+        global: &GlobalScope,
+        name: DOMString,
+        extensions: Heap<*mut JSObject>,
+        adapter: WebGPUAdapter,
+    ) -> DomRoot<GPUAdapter> {
+        reflect_dom_object(
+            Box::new(GPUAdapter::new_inherited(name, extensions, adapter)),
+            global,
+            GPUAdapterBinding::Wrap,
+        )
+    }
+}
+
+impl GPUAdapterMethods for GPUAdapter {
+    // https://gpuweb.github.io/gpuweb/#dom-gpuadapter-name
+    fn Name(&self) -> DOMString {
+        self.name.clone()
+    }
+
+    // https://gpuweb.github.io/gpuweb/#dom-gpuadapter-extensions
+    fn Extensions(&self, _cx: SafeJSContext) -> NonNull<JSObject> {
+        NonNull::new(self.extensions.get()).unwrap()
+    }
+}