qtdemux: Use the tfdt decode time on byte streams when it's significantly different than the time in the last sample
qtdemux: Use the tfdt decode time on byte streams when it's significantly different than the time in the last sample

We consider there's a sifnificant difference when it's larger than on second
or than half the duration of the last processed fragment in case the latter is
larger.

https://bugzilla.gnome.org/show_bug.cgi?id=754230

hizukiayaka/gst-plugins-good,pexip/gst-plugins-good,pexip/gst-plugins-good,stfl/gst-plugins-good,pexip/gst-plugins-good,GrokImageCompression/gst-plugins-good,hizukiayaka/gst-plugins-good,pexip/gst-plugins-good,hizukiayaka/gst-plugins-good,stfl/gst-plugins-good,StreamUtils/gst-plugins-good,GStreamer/gst-plugins-good,StreamUtils/gst-plugins-good,GrokImageCompression/gst-plugins-good,hizukiayaka/gst-plugins-good,GrokImageCompression/gst-plugins-good,stfl/gst-plugins-good,GStreamer/gst-plugins-good,GStreamer/gst-plugins-good,GStreamer/gst-plugins-good,StreamUtils/gst-plugins-good,GrokImageCompression/gst-plugins-good,pexip/gst-plugins-good,StreamUtils/gst-plugins-good,stfl/gst-plugins-good