[Mesa-dev] Move try_emit_* methods to bool return type

[Kai Wasserbäch]

[Please CC me on all replies, I'm not subscribed to mesa-dev.]

Dear Ian, dear Bryan,
the following two patches incorporate the wishes of Ian ([0]) wrt moving the
try_emit_* methods to bool from GLboolean.

The second patch adds the documentation requested in [0], though I'm not sure,
whether that is how you like/prefer it. Any hints/tips on how to improve the
second patch would be very welcome.

Kind regards,
Kai Wasserbäch