On Windows and macOS always use the proper monotonic clock, including
for gst_util_get_timestamp(), and initialize its state only once.
Also on macOS use clock_gettime() for the realtime clock, if available
instead of always falling back to GLib.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/4658>
We already have functions to generate a stream-id from pads but in the
end those pads are not even used in most cases. This adds functions to
generate a stream-id even before creating the source pads for the
element that is going to use it. For example a demuxer that is properly
implements the GstStream/GstStreamCollection API will not have a Pad but
already needs to generate a stream-id.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/3160>
GLib guarantees libintl is always present, using proxy-libintl as
last resort. There is no need to mock gettex API any more.
This fix static build on Windows because G_INTL_STATIC_COMPILATION must
be defined before including libintl.h, and glib does it for us as part
as including glib.h.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/2028>
