struct WireResultUnwrap

|WireResultUnwrap| is a template which will be specialized by generated code

to provide the type that should be returned by the |Unwrap|, |value|, and

dereference operator accessors on |BaseWireResult|. The template is not

available for methods with an empty return value and no error, since those do

not provide |Unwrap| methods.

The generated specialization will contain a single type alias called |Type|

which is the type that will be used in the |Unwrap| and related methods of

the |WireResult| and |WireUnownedResult|.

For a method without error syntax, the |Type| will be the return type of the

method specified in the FIDL file. For a method with error syntax, |Type|

will be a |fit::result| of the error type specified in the FIDL file and a

pointer to the return type (if the return type is not empty).