Add tests for this.

winedump: Use the DEFINE_THISCALL_WRAPPER macro instead of the GET_THIS macro for functions with __thiscall calling convention.

Wine doesn't use GET_THIS but DEFINE_THISCALL_WRAPPER.

The header file generated with "winedump spec" without the "-c" option
just includes other headers.

rpcrt4: The initialisation of [out] variables in the stubless code must be after the unmarshaling of [in] and [in, out] variables has been completed.

This is because the size of an [out] variable could depend on a
conformance value stored in an unmarshalled [in] or [in,out] variable.