message: Avoid crash if mapped memory is changed while diffing
diff: @@ -1147,6 +1147,14 @@ VkResult WrappedVulkan::vkQueueSubmit(VkQueue queue, uint32_t submitCount,
  else
  diffEnd = (size_t)state.mapSize;
  + // sanitise diff start/end. Since the mapped pointer might be written on another thread
  + // (or even the GPU) this could cause a difference to appear and disappear transiently. In
  + // this case FindDiffRange could find the difference when locating the start but not find
  + // it when locating the end. In this case we don't need to write the difference (the
  + // application is responsible for ensuring it's not writing to memory the GPU might need)
  + if(diffEnd <= diffStart)
  + found = false;
  +
  if(found)
  {
  // MULTIDEVICE should find the device for this queue.
  