Formerly, once seek is done, decoder drops P-frames until I-frame arrives.
But since the commits landed, it doesn't drop P-frame and does try to
decode it continuously because active_sps is still alive. See ensure_sps function.
But there are prev_frames and prev_ref_frames reset already, then it
causes assertion.
So it's necessary to reset active_sps/pps also in reset method.
vaapisink: keep handle_events flag except that if user want to set
When state of vaapisink is changed from PLAYING to NULL, the handle_events
flag is set to FALSE, and never recovered, and then event thread is never
going to run.
So we should allow to set the flag only when users try it.
libs: window: x11: fix src rect info when using vpp
Since we started using VPP in VaapiWindowX11, we need to care about
the case that src rect and window's size are different.
So, once VPP has converted to other format, we should honor the
size of the VPP's surface as source rect. Otherwise, it is cropped
according the previous size of the source rect.
