pad: Detect, fix and warn when sticky events are in wrong order
pad: Detect, fix and warn when sticky events are in wrong order

We can prevent buggy element from causing other elements to fail or crash
by sorting sticky event at insertion. In this case, we also warn as this
is not supposed to happen.

See: https://bugzilla.gnome.org/show_bug.cgi?id=688188

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