mesa: In core profile, refuse to draw unless a VAO is bound.
mesa: In core profile, refuse to draw unless a VAO is bound.

Core profile requires a non-default VAO to be bound.  Currently, calls
to glVertexAttribPointer raise INVALID_OPERATION unless a VAO is bound,
and we never actually get any vertex data set.  Trying to draw without
any vertex data can only cause problems.  In i965, it causes a crash.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=76400
Signed-off-by: Kenneth Graunke <bd2562f754ec92342f93f61c25d731e290a2ffa8@whitecape.org>
Reviewed-by: Ian Romanick <2b237cafb16dc45038e85df6c85e74e6d899eba9@intel.com>
Cc: 59f39c0db42d4479a46b02d4d2bc11120e37bb44@lists.freedesktop.org

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