[BEAM-4069] Gracefully deserialize empty options structs

[bsidhom]

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[bsidhom]

R: @kennknowles

[bsidhom]

If I'm reading the Jenkins output correctly, this appears to be failing due to ERROR: beam2 is offline; cannot locate JDK 1.8 (latest). I'm not sure if it even attempted to run any tests.

[bsidhom]

R: @tgroh

[tgroh]

Can this not be pulled up some? e.g.

PipelineOptions options;
if (rawOptionsNode == null || rawOptionsNode.isNull()) {
  options = PipelineOptionsFactory.create(); // or new ProxyInvocationHandler..., but I believe these to be equivalent
} else {
  // code
  options = ProxyInvocationHandler...
}
ValueProvider.RuntimeValueProvider.setRuntimeOptions(options)
return options;

Because the two if statements aren't independent - so we can just glom them together and have a more obvious path through the method.

[bsidhom]

As it turns out, the second if statement is completely redundant. ;)

I wasn't confident about the equivalence between an empty ProxyInvocationHandler reconstruction and PipelineOptionsFactory.create(), so I've left that as it was.

[tgroh]

Cool LGTM