Initial implementation of GPUQueue

Added WebIDL bindings for `GPUQueue`.
Implemented the `submit` function of `GPUQueue` and `defaultQueue` function of `GPUDevice`.

components/script/dom/webidls/GPUQueue.webidl

@@ -0,0 +1,18 @@
+/* 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/. */
+
+// https://gpuweb.github.io/gpuweb/#gpuqueue
+[Exposed=(Window, DedicatedWorker), Serializable, Pref="dom.webgpu.enabled"]
+interface GPUQueue {
+    void submit(sequence<GPUCommandBuffer> commandBuffers);
+
+    // GPUFence createFence(optional GPUFenceDescriptor descriptor = {});
+    // void signal(GPUFence fence, unsigned long long signalValue);
+
+    // void copyImageBitmapToTexture(
+    //     GPUImageBitmapCopyView source,
+    //     GPUTextureCopyView destination,
+    //     GPUExtent3D copySize);
+};
+GPUQueue includes GPUObjectBase;