[Payment Request] Completes refactor of abstracting away all credit cards

This CL completes the refactoring of Payment Request on iOS such that all
credit card objects (not including the one used in the card editor) are now
represented as PaymentInstrument objects. This paves the way for introducing
alternative forms of payment methods such as iOS Native Applications. Note
that a result delegate created in the AutofillPaymentInstrument class within
the components folder is now being used as the result delegate for
FullCardRequester. In the future we can remove more code from iOS to rely
more heavily on some of the processes that are taken care of in that
delegate (such as address normalization) however for this CL I wanted to
keep the flow for grabbing payment method details as similar as possible
while still abstracting away the credit cards.

Bug: 602666
Change-Id: I920684c924fb111d769dfabce212b96b006ac94d
Reviewed-on: https://chromium-review.googlesource.com/546918
Commit-Queue: Randall Raymond <[email protected]>
Reviewed-by: mahmadi <[email protected]>
Cr-Commit-Position: refs/heads/master@{#484357}
27 files changed