An inactive pad is a pad which, in live mode, hasn't yet received
a first buffer, but has been waited on at least once.
Exposing API to support this behaviour allows users of aggregator
subclasses to request pads, and not start pushing data on those
immediately, while avoiding systematic timeouts.
Subclasses must check in explicitly to this behavior, most likely
by exposing a user-facing property, and must check whether a pad
needs ignoring when aggregating. That is because by design,
aggregator subclasses don't get a list of "ready" pads, but instead
directly iterate element->sinkpads.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/867>
Introduces a `libraries` variable that contains all libraries in a
list with the following format:
``` meson
libraries = [
[pkg_name, {
'lib': library_object
'gir': [ {full gir definition in a dict } ]
],
....
]
```
It therefore refactors the way we build the gir so that we can reuse the
same information to build them against 'gstreamer-full' in gst-build
when linking statically
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/1093>
