Ensure that the AuthCode gets set correctly.

[lukezbihlyj]

This fixes a bug where the AuthCode will always be null even when RequestAuthCode is enabled in the global configuration. Tested in an app built with Unity 2017 on a real iOS device.

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[lukezbihlyj]

I signed it!

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CLAs look good, thanks!

[claywilkinson]

Great Catch! thanks!