[CP staging] Revert "Remove useDocumentTitle cleanup to fix tab title race condition"

[grgia]

Reverts #85473

$ #86087

[melvin-bot]

@MarioExpensify Please copy/paste the Reviewer Checklist from here into a new comment on this PR and complete it. If you have the K2 extension, you can simply click: [this button]

[chatgpt-codex-connector]

💡 Codex Review

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Reviewed commit: 68737dca1b

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[chatgpt-codex-connector]

Don't reset the global tab title in the focus cleanup

In our React Navigation 7 setup, the function returned from useFocusEffect is an effect cleanup, not a blur-only handler. Calling setPageTitle('') here mutates the shared currentPageTitle in src/libs/UnreadIndicatorUpdater/updateUnread/index.ts, so when the user switches between two screens that both use useDocumentTitle (for example HomePage, SearchPage, or ReportScreen), the outgoing screen can clear the title after the incoming screen has already focused. Because the document title is applied asynchronously in updateDocumentTitle(), this leaves the browser tab stuck on CONFIG.SITE_TITLE/New Expensify instead of the new page title, reintroducing the split-pane title race this hook just stopped having.

Useful? React with 👍 / 👎.

[NikkiWines]

👍

[mananjadhav]

Reverting the PR will cause #85352. Hence I was a bit concerned on straight revert.

[yuwenmemon]

AI is going around in circles: #85473

[yuwenmemon]

I think we should move forward with what @MelvinBot proposed here instead: #86087 (comment)

Otherwise, we'll just go back to a point where we cause a different blocker.

[MelvinBot]

I've created a separate draft PR implementing the proposed fix instead of a straight revert: #86142

This adds a clearPageTitle() function that resets the title variable synchronously without triggering updateDocumentTitle(), avoiding both the stale RHP title bug and the "New Expensify" flash from the original cleanup.

[yuwenmemon]

Let's go with the alternative: #86142

Also, I would say this isn't a blocker since it's not a major deviation from the "bugginess" in production