Moves preheader out of paypalexpress check

[JarrydLong]

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Changes proposed in this Pull Request:

Returning from PayPal results in you still having to click the Confirm Payment button if you don't have PayPal Express as the primary gateway.

This change moves it out of the if statement and should be okay as we check in that preheader function if the order's gateway is PPExpress and if not, return.

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