[MBL-1422] Handle errors without always dismissing

[ifosli]

📲 What

Don't dismiss the post campaign VC if there's an error caused by trying to add a new card.

Note: There are other categories of errors that also don't need to dismiss the VC (for example, if a user fails to authenticate a 3DS card). However, because we're currently planning to combine our checkout flows and get rid of the "confirm details" page, I didn't think it was worth spending a lot of extra time on this now.

🤔 Why

Needing to restart checkout in these cases is a little annoying.

🛠 How

I refactored the messageBannerView to optionally be in charge of dismissing the vc. That way, we can decide if the error should lead to dismissing the VC when a specific error is displayed to the user.

👀 See

Jira

Before 🐛	After 🦋

✅ Acceptance criteria

• Errors while adding a new card don't restart checkout
• All other errors during late pledge will still restart checkout

[ifosli]

I didn't add any new tests around dismissType - I don't think our code is structured to make it easy to capture when view controllers dismiss in tests (please correct me if I'm wrong about that!). Alternatively, I could move all the dismiss logic into the view controller, but that would be a bigger refactor than I was hoping for. Open to suggestions here!

[scottkicks]

LGTM

Are we confident that we don't need to create a new checkout from Confirm Details after this error. I'm like 90% that's true, but I tend to get paranoid in this flow 😅

[scottkicks]

minor nit: maybe bannerToParentVC is a clearer name for this case?

[ifosli]

I've renamed this to just bannerAndViewController - I think that we were thinking of the "parent vc" differently (in my mind it's the view controller that's getting dismissed, since it's the parent of the message banner). I think the new name is clearer for both of us!

[ifosli]

LGTM

Are we confident that we don't need to create a new checkout from Confirm Details after this error. I'm like 90% that's true, but I tend to get paranoid in this flow 😅

I double-checked the code and we don't even give stripe the checkout id when we're adding a new card (we give the project and late pledge vs crowdfunding pledge context), so there's no reason to go recreate the checkout id if adding the card goes wrong!