message: Updated DotNet interop.
diff: @@ -26,7 +26,7 @@ extern "C"
  if (service == nullptr)
  {
  Nrt_setErrMsgIsNullptrInternal();
  - return NRT_FAILURE_NULL_ARGUMENT_PROVIDED;
  + return NRT_FAILURE_NULL_INSTANCE_PROVIDED;
  }
  NovelRT::DotNet::RuntimeService* cService = reinterpret_cast<NovelRT::DotNet::RuntimeService*>(service);
  @@ -39,7 +39,7 @@ extern "C"
  if (service == nullptr)
  {
  Nrt_setErrMsgIsNullptrInternal();
  - return NRT_FAILURE_NULL_ARGUMENT_PROVIDED;
  + return NRT_FAILURE_NULL_INSTANCE_PROVIDED;
  }
  NovelRT::DotNet::RuntimeService* cService = reinterpret_cast<NovelRT::DotNet::RuntimeService*>(service);
  @@ -67,7 +67,7 @@ extern "C"
  if (service == nullptr)
  {
  Nrt_setErrMsgIsNullptrInternal();
  - return NRT_FAILURE_NULL_ARGUMENT_PROVIDED;
  + return NRT_FAILURE_NULL_INSTANCE_PROVIDED;
  }
  NovelRT::DotNet::RuntimeService* cService = reinterpret_cast<NovelRT::DotNet::RuntimeService*>(service);
  @@ -80,7 +80,7 @@ extern "C"
  if (service == nullptr)
  {
  Nrt_setErrMsgIsNullptrInternal();
  - return NRT_FAILURE_NULL_ARGUMENT_PROVIDED;
  + return NRT_FAILURE_NULL_INSTANCE_PROVIDED;
  }
  NovelRT::DotNet::RuntimeService* cService = reinterpret_cast<NovelRT::DotNet::RuntimeService*>(service);
  @@ -105,7 +105,13 @@ extern "C"
  NrtResult Nrt_RuntimeService_freeString(NrtRuntimeServiceHandle service, const char* str)
  {
  - if (service == nullptr || str == nullptr)
  + if (service == nullptr)
  + {
  + Nrt_setErrMsgIsNullptrInternal();
  + return NRT_FAILURE_NULL_INSTANCE_PROVIDED;
  + }
  +
  + if (str == nullptr)
  {
  Nrt_setErrMsgIsNullptrInternal();
  return NRT_FAILURE_NULL_ARGUMENT_PROVIDED;
  @@ -133,7 +139,13 @@ extern "C"
  NrtResult Nrt_RuntimeService_getInkService(NrtRuntimeServiceHandle service, NrtInkServiceHandle* outputInkService)
  {
  - if (service == nullptr || outputInkService == nullptr)
  + if (service == nullptr)
  + {
  + Nrt_setErrMsgIsNullptrInternal();
  + return NRT_FAILURE_NULL_INSTANCE_PROVIDED;
  + }
  +
  + if (outputInkService == nullptr)
  {
  Nrt_setErrMsgIsNullptrInternal();
  return NRT_FAILURE_NULL_ARGUMENT_PROVIDED;
  