The normal functions are always useful to have for bindings, especially
runtime-created bindings like Seed or new GObject-Introspection based
Python bindings.
Check when we need to touch the metadata of the output buffer after selecting
the output buffer so that we have everything in one place.
Also take flags and timestamp modifications into account.
When we have the same input as output caps, reuse the input caps object. After
the caps refcounting has been sorted out now, we can finally enable this
optimisation.
Without this, we risked:
* Checking the flushing state on an unexisting list
* Not setting the flushing state on pads that had just been added
Partially fixes#590056
Return FALSE in basesrc's default query handler when we get a SEEKING query for
a format that's not the one the source operates in. Previously (ie. before, in
the git version) we would return TRUE in that case and seekable=FALSE, which
is more correct, but causes backwards compatibility problems. (Before that
we would change the format of the query when answering, which was completely
broken since callers don't expect that or check for it). Since the SEEKING
query is a fairly recent addition, not all demuxers, parsers and decoders
implement it yet, in which case any SEEKING query by an application will
just be passed upstream where it will then be handled by basesrc. Now, if
e.g. totem does a SEEKING query for TIME format and we have a demuxer that
doesn't implement the query, basesrc would answer it with seekable=FALSE in
most cases, and totem can only take that as authoritative answer, not knowing
that the demuxer doesn't implement the SEEKING query. To avoid this, we make
basesrc return FALSE to SEEKING queries in unhandled formats. That way
applications like totem can fall back on assuming seekability depending on
whether a duration is available, or somesuch. Downstream elements doing
such queries are likely to equate an unhandled query with a non-seekable
response as well, so this should be an acceptable fix for the time being.
See #584838, #588944, #589423 and #589424.
Clarify byte reader docs a bit: offset is relative to the current
position of the reader, not to the start of the data. Also, the
examples in both the adapter docs and the byte reader docs have
the mask and pattern arguments swapped (see #587561). Spotted
by Carl-Anton Ingmarsson.
