2.7.6

[ianrumac]

Changes in this pull request

• Improve billing resillience and recovery
• Fix concurrency issue with product loads on early starts
• Fix concurrency issue with identity manager causing locks
• Fix bug with params not being templated into second presentation

Checklist

• All unit tests pass.
• All UI tests pass.
• Demo project builds and runs.
• I added/updated tests or detailed why my change isn't tested.
• I added an entry to the CHANGELOG.md for any breaking changes, enhancements, or bug fixes.
• I have run ktlint in the main directory and fixed any issues.
• I have updated the SDK documentation as well as the online docs.
• I have reviewed the contributing guide

Greptile Summary

This PR addresses billing resilience, concurrency, and presentation correctness issues. Key improvements include:

1. A ProductState sealed class + deferred-based coordination in StoreManager to prevent duplicate concurrent product fetches
2. Product retry logic in PaywallRequestManager for paywalls whose products failed during preload
3. A critical fix in PaywallViewState.ResetPresentationPreparations that corrects flag reset values for proper params templating on second presentation
4. Billing cache improvements in GoogleBillingWrapper to only cache permanent BillingNotAvailable errors
5. A timeout flow refactor in PaywallView to avoid NoSuchElementException

Sequence Diagram

sequenceDiagram
    participant Caller1
    participant Caller2
    participant StoreManager
    participant ProductsByFullId as productsByFullId (ConcurrentHashMap)
    participant Billing

    Note over Caller1,Billing: Concurrent product fetch with deferred coordination

    Caller1->>StoreManager: fetchOrAwaitProducts({"prod1"})
    StoreManager->>ProductsByFullId: computeIfAbsent("prod1") → Loading(deferred1)
    StoreManager->>Billing: awaitGetProducts({"prod1"})

    Caller2->>StoreManager: fetchOrAwaitProducts({"prod1"})
    StoreManager->>ProductsByFullId: computeIfAbsent("prod1") → Loading(deferred1) [existing]
    StoreManager->>StoreManager: add deferred1 to loading list

    Billing-->>StoreManager: {prod1: StoreProduct}
    StoreManager->>ProductsByFullId: put("prod1", Loaded(product))
    StoreManager->>StoreManager: deferred1.complete(product)
    StoreManager-->>Caller1: {prod1: product}
    StoreManager-->>Caller2: {prod1: product} (via awaited deferred)

    Note over Caller1,Billing: Retry after transient error

    Caller1->>StoreManager: fetchOrAwaitProducts({"prod1"})
    StoreManager->>ProductsByFullId: computeIfAbsent("prod1") → Error(e) [existing]
    StoreManager->>ProductsByFullId: put("prod1", Loading(deferred2)) [non-atomic replace!]
    StoreManager->>Billing: awaitGetProducts({"prod1"})
    Billing-->>StoreManager: {prod1: StoreProduct}
    StoreManager-->>Caller1: {prod1: product}

Loading

_{Last reviewed commit: 538a40e}

Greptile also left 4 inline comments on this PR.