Backport fix for crashes and invalid writes in totem from libvisual
in -base, to minimise differences to version in -base and to make
sure the bug doesn't sneak back in later when the base class is
made public.
The shader code looks like it makes assumptions that are not
necessarily always true, even if they're true for now for the
existing elements, namly that pixel stride is 4, for example.
See https://bugzilla.gnome.org/show_bug.cgi?id=683527
gst_query_set_nth_allocation_pool() requires there to be a pool in the
query already. This is not always the case when we get the query from
upstream. Use gst_query_add_allocation_pool() instead in such case.
https://bugzilla.gnome.org/show_bug.cgi?id=681719
The current code is memsetting the GstVideoFrame.data address to 0s (which
causes a segfault). This member is actually an array of data buffers (one for
each plane). This fix iterates over each data plane to clear them all.
https://bugzilla.gnome.org/show_bug.cgi?id=695655
Add support for GstVideoMeta and GstVideoFrame. Remove some redundant fields
that are also in GstVideoInfo. Don't disable the shader code, it does not
look broken.
