Drivers can return VK_ERROR_OUT_OF_DATE_KHR from vkQueuePresentKHR, and
we should resize the image in this case, as well as when getting it back
from vkAcquireNextImageKHR.
Instead of resetting two command buffers, now we only have to call
vkResetCommandPool once at the start of a frame.
NV's recommends using one pool per frame/thread. May offer a very small
boost in performance on some systems.