selector: merge the tags
selector: merge the tags

Merge the tags received on the input-selector sinkpads instead of only keeping
the last one we saw.

shelsonjava/gstreamer,mrchapp/gstreamer,cablelabs/gstreamer,jpakkane/gstreamer,Distrotech/gstreamer,drothlis/gstreamer,krichter722/gstreamer,mparis/gstreamer,mparis/gstreamer,cfoch/gstreamer,StreamUtils/gstreamer,ylatuya/gstreamer,drothlis/gstreamer,mparis/gstreamer,shelsonjava/gstreamer,ahmedammar/platform_external_gst_gstreamer,ensonic/gstreamer,ylatuya/gstreamer,lovebug356/gstreamer,justinjoy/gstreamer,jpxiong/gstreamer,krichter722/gstreamer,Lachann/gstreamer,mrchapp/gstreamer,collects/gstreamer,magcius/gstreamer,mrchapp/gstreamer,ensonic/gstreamer,drothlis/gstreamer,StreamUtils/gstreamer,mrchapp/gstreamer,ahmedammar/platform_external_gst_gstreamer,drothlis/gstreamer,krieger-od/gstreamer,mparis/gstreamer,centricular/gstreamer,ahmedammar/platform_external_gst_gstreamer,lubosz/gstreamer,surround-io/gstreamer,justinjoy/gstreamer,krichter722/gstreamer,krieger-od/gstreamer,ahmedammar/platform_external_gst_gstreamer,justinjoy/gstreamer,magcius/gstreamer,cfoch/gstreamer,ylatuya/gstreamer,lovebug356/gstreamer,Lachann/gstreamer,centricular/gstreamer,surround-io/gstreamer,Distrotech/gstreamer,jpxiong/gstreamer,centricular/gstreamer,lubosz/gstreamer,Distrotech/gstreamer,ensonic/gstreamer,surround-io/gstreamer,jpakkane/gstreamer,cfoch/gstreamer,lubosz/gstreamer,collects/gstreamer,lubosz/gstreamer,magcius/gstreamer,jpxiong/gstreamer,magcius/gstreamer,collects/gstreamer,lovebug356/gstreamer,lovebug356/gstreamer,cfoch/gstreamer,krieger-od/gstreamer,surround-io/gstreamer,cablelabs/gstreamer,jpakkane/gstreamer,StreamUtils/gstreamer,magcius/gstreamer,centricular/gstreamer,krichter722/gstreamer,shelsonjava/gstreamer,mparis/gstreamer,justinjoy/gstreamer,surround-io/gstreamer,krieger-od/gstreamer,Lachann/gstreamer,ensonic/gstreamer,jpxiong/gstreamer,collects/gstreamer,ylatuya/gstreamer,drothlis/gstreamer,lovebug356/gstreamer,cfoch/gstreamer,centricular/gstreamer,jpakkane/gstreamer,lubosz/gstreamer,collects/gstreamer,ensonic/gstreamer,StreamUtils/gstreamer,Distrotech/gstreamer,Distrotech/gstreamer,justinjoy/gstreamer,ylatuya/gstreamer,StreamUtils/gstreamer,jpakkane/gstreamer,Lachann/gstreamer,krichter722/gstreamer,cablelabs/gstreamer,cablelabs/gstreamer,shelsonjava/gstreamer,jpxiong/gstreamer,ahmedammar/platform_external_gst_gstreamer,krieger-od/gstreamer,mrchapp/gstreamer,Lachann/gstreamer,shelsonjava/gstreamer,cablelabs/gstreamer