Using the mesa vulkan driver, if you acquire an image from a
swapchain using a finite timeout (x11_acquire_next_image_poll_x11),
it will occasionally lock, calling xcb_poll_for_special_event in
a loop until the timeout expires.
Call _xcb_in_read() once from the polling functions for special
events and replies, in the same way as xcb_poll_for_event.
Signed-off-by: David McFarland <corngood@gmail.com>
Signed-off-by: Uli Schlachter <psychon@znc.in>
fad81b6342