Use bindingEquals() generated for interfaces

Use bindingEquals() generated for interfaces

As we are generating a default implementation of equals(), we
can defer to that implementation from runtime-generated proxies.

This results in:
- consistent results between compile-time and runtime implementations
- faster startup time, as there is only one dispatch implementation
- lower memory overhead, as runtime-generated classes are smaller
- more maintainable code, as the implementation can be examined at
  compile-time

Since this is the last method that references properties, we also
get to clean up some of the knowledge of how these need to be ordered.

JIRA: MDSAL-474
Change-Id: I1a0ca93755e670b7d8fa0834f87ee7a828843aa6
Signed-off-by: illia.ihushev <illia.ihushev@pantheon.tech>
Signed-off-by: Robert Varga <robert.varga@pantheon.tech>