vulkan: never flush the scheduler from the async present thread

Swapchain::AcquireNextImage waits for the main scheduler's tick of the
image's last use; when that tick was not submitted yet, Scheduler::Wait
flushed, recording into the current chunk on the present thread while
the GPU thread recorded into it too (corrupt command buffers, crashes
in vkCmdEndRenderPass and in CommandChunk::Record). With async
presentation the present thread now waits up to 20 ms for the
recording thread to submit the tick, and goes on without the wait
otherwise (the copy to the swapchain has its own fences).

0 files changed, 0 insertions, 0 deletions