)

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## **Description**

<!--
Write a short description of the changes included in this pull request,
also include relevant motivation and context. Have in mind the following
questions:
1. What is the reason for the change?
2. What is the improvement/solution?
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Social login (Google / Apple) users who completed onboarding before the
`ANALYTICS_PREFERENCE_SELECTED` event was emitted on the
marketing-consent
screen never had that event fired for them. This PR introduces a
one-time
post-rehydration backfill so those users are counted correctly in
analytics.

**How it works (three-step design kept intentionally pure):**

1. **Migration 131** – runs at startup before the Redux store is live.
If the
persisted state contains a `SeedlessOnboardingController.authConnection`
   value, it writes a
marker into
`onboarding.seedless.pendingSocialLoginMarketingConsentBackfill`.
The migration never fires analytics itself; it only stamps the persisted
   state so the side effect can be done safely after rehydration.

2. **Redux slice** – a new
`SET_PENDING_SOCIAL_LOGIN_MARKETING_CONSENT_BACKFILL`
action/reducer/selector manages the marker in
`state.onboarding.seedless`.

3. **Saga** – `backfillSocialLoginMarketingConsent` runs once inside
`startAppServices` (after `setAppServicesReady`). It reads the marker
from
   the live store, fires `ANALYTICS_PREFERENCE_SELECTED` with
`saveDataRecording: true`, calls `updateDataRecordingFlag`, and clears
the
marker. If the marketing consent is no longer enabled at run time (e.g.
user
toggled it off between migrations) the marker is cleared without sending
any
analytics. If `trackEvent` throws, the marker is left in place so a
future
   run can retry.
## **Changelog**

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CHANGELOG entry: null


## **Related issues**

Fixes:

## **Manual testing steps**

```gherkin
Feature: One-time marketing consent analytics backfill for social login users

  Background:
    Given I have a device with a previously installed version of MetaMask Mobile
    And I am a social login (Google or Apple) user
    And I previously accepted marketing data collection during onboarding

  Scenario: backfill event fires once on first launch after upgrade
    Given the app has not yet run migration 129
    And state.security.dataCollectionForMarketing is true
    And state.engine.backgroundState.SeedlessOnboardingController.authConnection is "google"

    When user launches the app and the store rehydrates
    Then migration 129 sets onboarding.seedless.pendingSocialLoginMarketingConsentBackfill to "google"
    And the backfill saga fires an ANALYTICS_PREFERENCE_SELECTED event with has_marketing_consent true
    And the pending marker is cleared to null
    And on subsequent app launches no duplicate event is fired

  Scenario: backfill is skipped when user has opted out of marketing consent
    Given state.security.dataCollectionForMarketing is false
    And state.engine.backgroundState.SeedlessOnboardingController.authConnection is "google"

    When user launches the app and the store rehydrates
    Then migration 129 does NOT set the pending marker
    And no ANALYTICS_PREFERENCE_SELECTED event is fired

  Scenario: stale marker is cleared without analytics when consent is revoked before launch
    Given the pending marker was set in a previous session (e.g. "google")
    And the user has since revoked marketing consent (dataCollectionForMarketing is false)

    When the app launches and the saga runs
    Then the pending marker is cleared to null
    And no ANALYTICS_PREFERENCE_SELECTED event is fired
```

## **Screenshots/Recordings**

<!-- If applicable, add screenshots and/or recordings to visualize the
before and after of your change. -->

### **Before**

<!-- [screenshots/recordings] -->

### **After**

<!-- [screenshots/recordings] -->

## **Pre-merge author checklist**

- [ ] I've followed [MetaMask Contributor
Docs](https://github.com/MetaMask/contributor-docs) and [MetaMask Mobile
Coding
Standards](https://github.com/MetaMask/metamask-mobile/blob/main/.github/guidelines/CODING_GUIDELINES.md).
- [ ] I've completed the PR template to the best of my ability
- [ ] I've included tests if applicable
- [ ] I've documented my code using [JSDoc](https://jsdoc.app/) format
if applicable
- [ ] I've applied the right labels on the PR (see [labeling
guidelines](https://github.com/MetaMask/metamask-mobile/blob/main/.github/guidelines/LABELING_GUIDELINES.md)).
Not required for external contributors.

## **Pre-merge reviewer checklist**

- [ ] I've manually tested the PR (e.g. pull and build branch, run the
app, test code being changed).
- [ ] I confirm that this PR addresses all acceptance criteria described
in the ticket it closes and includes the necessary testing evidence such
as recordings and or screenshots.




<!-- CURSOR_SUMMARY -->
---

> [!NOTE]
> **Medium Risk**
> Adds a new persisted onboarding marker, a state migration, and a
login-triggered saga that sends analytics/updates consent flags;
mistakes could cause missed or duplicate analytics and unexpected
consent state changes after rehydration.
> 
> **Overview**
> Adds a one-time *post-rehydration* analytics backfill for legacy
social login (Google/Apple) users who never emitted
`ANALYTICS_PREFERENCE_SELECTED` for marketing consent.
> 
> This introduces a new onboarding state marker
(`pendingSocialLoginMarketingConsentBackfill`) with
action/reducer/selector support, sets it via new `migration 131` based
on `SeedlessOnboardingController.authConnection`, and runs a new
`backfillSocialLoginMarketingConsentSaga` after `LOGIN` to optionally
query OAuth marketing opt-in, emit the analytics identify/event (with
`saveDataRecording: true`), update recording via
`updateDataRecordingFlag`, then clear the marker and sync
`setDataCollectionForMarketing`.
> 
> Wallet deletion now also clears the marker, and tests were
added/updated across onboarding reducer/selectors, migrations, and
sagas.
> 
> <sup>Reviewed by [Cursor Bugbot](https://cursor.com/bugbot) for commit
2a0bacd. Bugbot is set up for automated
code reviews on this repo. Configure
[here](https://www.cursor.com/dashboard/bugbot).</sup>
<!-- /CURSOR_SUMMARY -->