It'll be interesting to see whether the same conclusion would be reached in an English court, but I'd be fairly confident that in the same circumstances it would.
However, I can see a whole new jurisprudence developing as to the interpretation of the meaning of different emojis - it's only a matter of time before the Supreme Court rules on whether a smiling emoji means "Yes, I'm happy to agree" or "You're 'avin' a larf!"
![Very Happy :D](./images/smilies/icon_e_biggrin.gif)
![Sad :(](./images/smilies/icon_e_sad.gif)