Functions-samples: PubSub example missing return value

[klevismino]

Hello @nicolasgarnier

I just noticed that the PubSub example code has no return value. I think there should be a Promise returned, otherwise you get the following error on Stackdriver Logs: "Function returned undefined, expected Promise or value"

[kariem]

Same here: Adding return 0; at the end of the function does not show the error message. See also discussion on Stackoverflow, specifically this comment:

From what I was told by the firebase support it sounds like things are going to remain this way.

Would you like a PR with the corresponding return statements added at the end of each method? Otherwise the current code produces errors.

[nicolasgarnier]

Thanks for the report! I've added some return null; in the sample