Revert "imagefreeze: Remove impossible error condition"
Revert "imagefreeze: Remove impossible error condition"

This reverts commit d46631c5c7312ad613397f8238c7a9714ae3ae94.

pad only handle EOS events but not EOS flow, and will push the buffer again
resulting in an assertion error. So we should not handle the buffer
and return EOS flow.

ikonst/gst-plugins-good,Kurento/gst-plugins-good,froggatt/gst-plugins-good-m,chamois94/gst-plugins-good,GrokImageCompression/gst-plugins-good,sebras/gst-plugins-good,GrokImageCompression/gst-plugins-good,StreamUtils/gst-plugins-good,StreamUtils/gst-plugins-good,ikonst/gst-plugins-good,froggatt/gst-plugins-good-m,Kurento/gst-plugins-good,stfl/gst-plugins-good,pexip/gst-plugins-good,Kurento/gst-plugins-good,Kurento/gst-plugins-good,GrokImageCompression/gst-plugins-good,GStreamer/gst-plugins-good,ikonst/gst-plugins-good,rawoul/gst-plugins-good,pexip/gst-plugins-good,StreamUtils/gst-plugins-good,pexip/gst-plugins-good,hizukiayaka/gst-plugins-good,chamois94/gst-plugins-good,chamois94/gst-plugins-good,rawoul/gst-plugins-good,sebras/gst-plugins-good,ikonst/gst-plugins-good,hizukiayaka/gst-plugins-good,sebras/gst-plugins-good,stfl/gst-plugins-good,GStreamer/gst-plugins-good,rawoul/gst-plugins-good,rawoul/gst-plugins-good,pexip/gst-plugins-good,GStreamer/gst-plugins-good,GrokImageCompression/gst-plugins-good,froggatt/gst-plugins-good-m,stfl/gst-plugins-good,StreamUtils/gst-plugins-good,froggatt/gst-plugins-good-m,Kurento/gst-plugins-good,sebras/gst-plugins-good,stfl/gst-plugins-good,hizukiayaka/gst-plugins-good,chamois94/gst-plugins-good,pexip/gst-plugins-good,GStreamer/gst-plugins-good,hizukiayaka/gst-plugins-good