Added WebIDL bindings for `GPUCommandEncoder`, `GPUCommandBuffer`, `GPUComputePassEncoder`, `GPUProgrammablePassEncoder`.
Implemented the `beginComputePass`, `copyBufferToBuffer` and `finish` functions of `GPUCommandEncoder`.
Implemented the `createCommandEncoder` function of `GPUDevice`.
Initial implementation of GPUBindGroup for WebGPU
Added WebIDL bindings for `GPUBindGroup`.
Implemented the `createBindGroup` function of `GPUDevice`
Renamed `GPUBindGroupBinding` to `GPUBindGroupBindings` and `GPUBufferBinding` to `GPUBufferBindings` in the WebIDL, because these names are already occupied.
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- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes addresses a part of #24706
cc @kvark @jdm @zakorgy
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Added WebIDL bindings for `GPUBindGroupLayout`, `GPUBindGroupLayoutDescriptor`, `GPUBindingType`, `GPUShaderStage`
and `GPUBindGroupLayoutBinding` (Note: The servo's codegen doesn't like the name, because its already occupied).
Implemented the `createBindGroupLayout` function of `GPUDevice`.
Added WebIDL bindings for GPUBuffer, GPUBufferDescriptor, GPUBufferUsage
Implemented the `createBuffer` and `createBufferMapped` functions of GPUDevice
Added the WebIDL bindigs for GPUDevice, GPUObjectDescriptorBase, GPUDeviceDescriptor, GPUObjectBase
Implemented the `requestDevice` function of `GPUAdapter`
