When present_wnmd_clear_window_flip is done, present_destroy_window
frees struct present_window_priv, and the events in the flip queue
become unreachable. So if we don't free them first, they're leaked.
Also drop the call to present_wnmd_set_abort_flip, which just sets a
flag in struct present_window_priv and thus can't have any observable
effect after present_destroy_window.
Closes: https://gitlab.freedesktop.org/xorg/xserver/-/issues/1042
Reviewed-by: Dave Airlie <airlied@redhat.com>
1bdedc8dbb