Resource leak in GPUCanvasContext::getSwapChainPreferredFormat

It appears that the new WGPUSwapChainImpl pointer returned by wgpuDeviceCreateSwapChain() does not get deleted; this causes AddressSanitizer to flag the leak. See the instance variable in the code snippet below:

  if (window->preferredSwapChainFormat == WGPUTextureFormat_Undefined) {
    WGPUSwapChainDescriptor descriptor;
    descriptor.nextInChain = nullptr;
    // returns always the same address, so we dont have to release this temp swapchain?
    descriptor.implementation = device->binding->GetSwapChainImplementation();
    WGPUSwapChain instance = wgpuDeviceCreateSwapChain(device->instance, nullptr, &descriptor);
    glfwPollEvents();
    window->preferredSwapChainFormat = device->binding->GetPreferredSwapChainTextureFormat();
  }

Start at GPUCanvasContext::getSwapChainPreferredFormat and inspect the instance variable created by wgpuDeviceCreateSwapChain(). Use AddressSanitizer to reproduce the reported leak, then verify that the temporary swap chain is released and the sanitizer no longer reports it.