message: Fix crash with fetching mesh output if no descriptor sets are bound
diff: @@ -1228,6 +1228,8 @@ void VulkanReplay::PatchReservedDescriptors(const VulkanStatePipeline &pipe,
  // was doing and the other sets are statically unused.
  setLayouts.resize(RDCMIN(pipe.descSets.size(), pipeDescSetLayouts.size()));
  + size_t boundDescs = setLayouts.size();
  +
  // need at least one set, if the shader isn't using any we'll just make our own
  if(setLayouts.empty())
  setLayouts.resize(1);
  @@ -1346,7 +1348,7 @@ void VulkanReplay::PatchReservedDescriptors(const VulkanStatePipeline &pipe,
  m_pDriver->vkAllocateDescriptorSets(dev, &descSetAllocInfo, descSets.data());
  // copy the data across from the real descriptors into our adjusted bindings
  - for(size_t i = 0; i < setLayouts.size(); i++)
  + for(size_t i = 0; i < boundDescs; i++)
  {
  if(pipe.descSets[i].descSet == ResourceId())
  continue;
  