Commands and events can define their argument type inline (default) or
by referring to another type ('boxed': true, since commit c818408e44
"qapi: Implement boxed types for commands/events", v2.7.0). The
unboxed inline definition is an (anonymous) struct type. The boxed
type may be a struct, union, or alternate type.
The latter is problematic: docs/interop/qemu-spec.txt requires the
value of the 'data' key to be a json-object, but any non-degenerate
alternate type has at least one branch that isn't.
Fortunately, we haven't made use of alternates in this context outside
tests/. Drop support for them.
QAPISchemaAlternateType.is_empty() is now unused. Drop it, too.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20190913201349.24332-4-armbru@redhat.com>
b22e86585b