fix(messaging): wire Firelog delivery metrics flush (startLoggingService)

[zwu52]

Intent

Ship a fix so FCM Web delivery metrics / Firelog logging actually runs after developers enable experimentalSetDeliveryMetricsExportedToBigQueryEnabled. Today stageLog only queues events in memory; startLoggingService was never started from production code, so _processQueue → _dispatchLogEvents never fired and no POST to play.google.com/log occurred. This PR wires startLoggingService from stageLog and when enabling export, uses an immediate first flush (INITIAL_LOG_FLUSH_DELAY_MS = 0) for easier verification while keeping subsequent batches on LOG_INTERVAL_IN_MS after dispatch.

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Summary

• stageLog: call startLoggingService(messaging) after enqueueing (idempotent).
• _setDeliveryMetricsExportedToBigQueryEnabled(..., true): call startLoggingService so the flush loop arms when users opt in.
• startLoggingService: first _processQueue delay 0; _dispatchLogEvents still reschedules with LOG_INTERVAL_IN_MS (24h).

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Root cause

startLoggingService had zero production call sites; only stageLog appended to logEvents, so Firelog fetch never ran.

b/503660323

[changeset-bot]

🦋 Changeset detected

Latest commit: a2c5f8b

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 3 packages

Name	Type
@firebase/messaging	Patch
firebase	Patch
@firebase/messaging-compat	Patch

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[gemini-code-assist]

Code Review

This pull request updates the messaging service to initiate the logging service immediately upon enabling delivery metrics or staging a log, while also reducing the initial flush delay to zero. Feedback highlights a logic issue where starting the service with an empty queue could cause a 24-hour delay for subsequent events. Additionally, there is a risk of data loss during asynchronous log dispatching and a recommendation to clear the log queue when metrics export is disabled to ensure data privacy and memory efficiency.

[github-actions]

Changeset File Check ✅

• No modified packages are missing from the changeset file.
• No changeset formatting errors detected.

[Doris-Ge]

Is there any integration unit test we can add? For example, in the test, we set deliveryMetricsExportedToBigQueryEnabled to true, and then trigger onPush to verify that the logs are sent to FireLog. This test would help us catch the original bug that startLoggingService was not called anywhere.

[zwu52]

Is there any integration unit test we can add? For example, in the test, we set deliveryMetricsExportedToBigQueryEnabled to true, and then trigger onPush to verify that the logs are sent to FireLog. This test would help us catch the original bug that startLoggingService was not called anywhere.

added on in the sw test.

[Doris-Ge]

I can't find a way to mark a resolved comment as unresolved. But in case you didn't see it, I posted another comment under this thread:
#9916 (comment)

[Doris-Ge]

I can't find a way to mark a resolved comment as unresolved. But in case you didn't see it, I posted another comment under this thread: #9916 (comment)

Looks like the link does not work as I expected. I meant this https://screenshot.googleplex.com/8au9ubxMhUaaAvg

Critique is definitely much better...

[zwu52]

I can't find a way to mark a resolved comment as unresolved. But in case you didn't see it, I posted another comment under this thread: #9916 (comment)

Looks like the link does not work as I expected. I meant this https://screenshot.googleplex.com/8au9ubxMhUaaAvg

Critique is definitely much better...

agreed. good catch. forgot to paste it after polishing with ai. added in the sw listener file where it is most approparte as the entrance point for looging

[hsubox76]

LG - is there a reported Github issue we can link users to in the release notes, to show what problem has been fixed, or was the bug discovered elsewhere?