message: Check ShaderModuleDescriptor->nextInChain
diff: namespace dawn_native {
  - MaybeError ValidateShaderModuleDescriptor(DeviceBase*, const ShaderModuleDescriptor*) {
  + MaybeError ValidateShaderModuleDescriptor(DeviceBase*, const ShaderModuleDescriptor* descriptor) {
  + DAWN_TRY_ASSERT(descriptor->nextInChain == nullptr, "nextInChain must be nullptr");
  // TODO(cwallez@chromium.org): Use spirv-val to check the module is well-formed
  return {};
  }
  