GL: tex_id is always zero after updating from 1.8 to 1.10

[Gottfried Haider]

Our code [1] is modeled after the testegl example in gst-omx. In 1.8,
in handling the "handoff" signal, we would retrieve a (nonzero) tex_id
from the GstBuffer we're handed.

With 1.10 the code doesn't throw any particular error, the callback is
still begin periodically executed - but the tex_id is always zero.

Any idea about what could have caused this change in behavior?

I am testing on macOS 10.11.6 with the gstreamer-1.0-1.10.0-x86_64
binary from the site.

Thanks in advance,
Gottfried