[paymentrequest] Fix spec nits based on implementation experience. (#51)

You can view, comment on, or merge this pull request online at:

  https://github.com/WICG/paymentrequest/pull/51

-- Commit Summary --

  * Move the synchronous argument validation from show() to constructor
  * If only one shippingOption is provided, the user shouldn't have to select it.
  * Make sure complete() can only be called once.

-- File Changes --

    M specs/paymentrequest.html (56)

-- Patch Links --

https://github.com/WICG/paymentrequest/pull/51.patch
https://github.com/WICG/paymentrequest/pull/51.diff

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Reply to this email directly or view it on GitHub:
https://github.com/WICG/paymentrequest/pull/51