segment: resurrect sanitizing start and stop for seeking
segment: resurrect sanitizing start and stop for seeking

cablelabs/gstreamer,mparis/gstreamer,krichter722/gstreamer,jpakkane/gstreamer,ensonic/gstreamer,surround-io/gstreamer,jpxiong/gstreamer,mparis/gstreamer,StreamUtils/gstreamer,lovebug356/gstreamer,lubosz/gstreamer,lovebug356/gstreamer,lovebug356/gstreamer,shelsonjava/gstreamer,mparis/gstreamer,Lachann/gstreamer,surround-io/gstreamer,shelsonjava/gstreamer,cfoch/gstreamer,StreamUtils/gstreamer,jpakkane/gstreamer,krieger-od/gstreamer,cfoch/gstreamer,cfoch/gstreamer,jpakkane/gstreamer,lovebug356/gstreamer,cfoch/gstreamer,krichter722/gstreamer,krichter722/gstreamer,krichter722/gstreamer,Lachann/gstreamer,krieger-od/gstreamer,centricular/gstreamer,mparis/gstreamer,jpxiong/gstreamer,krieger-od/gstreamer,centricular/gstreamer,StreamUtils/gstreamer,centricular/gstreamer,lubosz/gstreamer,Lachann/gstreamer,shelsonjava/gstreamer,StreamUtils/gstreamer,lubosz/gstreamer,centricular/gstreamer,Lachann/gstreamer,centricular/gstreamer,jpxiong/gstreamer,ensonic/gstreamer,lovebug356/gstreamer,surround-io/gstreamer,krieger-od/gstreamer,jpakkane/gstreamer,lubosz/gstreamer,surround-io/gstreamer,cablelabs/gstreamer,lubosz/gstreamer,jpakkane/gstreamer,shelsonjava/gstreamer,ensonic/gstreamer,StreamUtils/gstreamer,jpxiong/gstreamer,ensonic/gstreamer,Lachann/gstreamer,cablelabs/gstreamer,shelsonjava/gstreamer,krichter722/gstreamer,ensonic/gstreamer,cablelabs/gstreamer,jpxiong/gstreamer,cfoch/gstreamer,mparis/gstreamer,cablelabs/gstreamer,surround-io/gstreamer,krieger-od/gstreamer