BINDINGS-23: Proposed resolution

[Simon Nash <oasis@cjnash.com>]

Section 2.2 defines how interfaces for services and references are
mapped to portTypes.  So, all the references to equivalence that are
mentioned in the issue are talking about equivalence relationships
between a service or reference's portType (possibly mapped) and a
portType in a WSDL service, port or binding.

The assembly spec talks about compatibility between the source
interface and target interface of a wire.  This isn't the case we
have here.  However, it makes sense to reuse this definition,
so I will propose the following wording for the Web Service binding
spec that delegates to the wording already in the assembly spec.

1. Change all these "equivalent" references to "compatible".

2. After line 100, add the following:

     A portType in a WSDL port is compatible with a portType in an
     SCA reference if and only if the WSDL portType would be a valid
     assembly wiring target interface for the reference portType's
     source interface.

     A portType in a WSDL port is compatible with a portType in an
     SCA service if and only if the service portType would be a valid
     assembly wiring target interface for the WSDL portType's
     source interface.

   Simon