[fidl][rust] Move error types into fidl_next

These types don't have a bind-specific replacement, and so can be used
from fidl_next_protocol directly.

Change-Id: Id1fa4c55c0c22d43292d886bec13c20ddaed1bf1
Reviewed-on: https://fuchsia-review.googlesource.com/c/fuchsia/+/1220024
Fuchsia-Auto-Submit: David Koloski <[email protected]>
Commit-Queue: David Koloski <[email protected]>
Reviewed-by: Ian McKellar <[email protected]>

Author: djkoloski

src/lib/fidl/rust_next/fidl_next/src/lib.rs

@@ -24,7 +24,8 @@
 pub use ::fidl_next_bind::*;
 pub use ::fidl_next_codec::*;
 pub use ::fidl_next_protocol::{
-    self as protocol, ProtocolError, RecvFuture, SendFuture, Transport,
+    self as protocol, FrameworkError, ProtocolError, RecvFuture, SendFuture, Transport,
+    WireFrameworkError,
 };
 
 /// Fuchsia-specific FIDL extensions.