For #11655: add leanplum event for installing an addon

[jhugman]

Fixes #11655.

This PR adds a metrics Event fired when the user has successfully installed an addon from the addon manager.

It further enables the event to be logged as a LeanPlum event. It is not enabled as a Glean event.

The data-review will occur in this PR.

Pull Request checklist

• [ ] Tests: This PR includes thorough tests or an explanation of why it does not
• [ ] Screenshots: This PR includes screenshots or GIFs of the changes made or an explanation of why it does not
• [ ] Accessibility: The code in this PR follows accessibility best practices or does not include any user facing features. In addition, it includes a screenshot of a successful accessibility scan to ensure no new defects are added to the product.

After merge

• Milestone: Make sure issues finished by this pull request are added to the milestone of the version currently in development.

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2. click Details next to "Taskcluster (pull_request)" after it appears and then finishes with a green checkmark,
3. click on the "Fenix - assemble" task, then click "Run Artifacts".
4. the APK links should be on the left side of the screen, named for each CPU architecture

[jhugman]

Request for data collection review form

All questions are mandatory. You must receive review from a data steward peer on your responses to these questions before shipping new data collection.

1. What questions will you answer with this data?

To measure how often addons are installed.

2. Why does Mozilla need to answer these questions? Are there benefits for users? Do we need this information to address product or business requirements?

This will drive the CFR/mobile marketing automation, this will aid feature discovery for the users.

3. What alternative methods did you consider to answer these questions? Why were they not sufficient?

• N/A (These are baseline metrics)

4. Can current instrumentation answer these questions?

• No, we are not tracking this for Glean, but we need access to them in Leanplum for mobile marketing automation usage.

5. List all proposed measurements and indicate the category of data collection for each measurement, using the Firefox data collection categories on the found on the Mozilla wiki.

• All data is Category 2.

6. How long will this data be collected?

This data will be present as long as the user ID exists in Leanplum. LeanPlum does not support expiry dates for probes, but the mobile engagement/marketing automation teams will track this. @cbonacuse is the first contact here.

7. What populations will you measure?

• All release, beta, and nightly users with telemetry enabled.

8. Please provide a general description of how you will analyze this data.

• Leanplum / Amplitude

9. Where do you intend to share the results of your analysis?

• Only on Leanplum, Amplitude and with mobile teams.

[eliserichards]

This looks great. Ready to merge pending data approval from @boek

[liuche]

I assume this was a copypasta error, but the data request is about tracking protection, not addon usage. Please update the request form! @jhugman

Data Review Form (to be filled by Data Stewards)

1. Is there or will there be documentation that describes the schema for the ultimate data set in a public, complete, and accurate way?

addon addition is documented in mma.md

2. Is there a control mechanism that allows the user to turn the data collection on and off?

Yes, Leanplum collection is covered by Fenix data controls

3. If the request is for permanent data collection, is there someone who will monitor the data over time?

We should review Leanplum probes every 6 mo, and @cbonacuse from Mobile Engagement will monitor. @cbonacuse is also looking into how we might get LeanPlum automatic expiry.

4. Using the category system of data types on the Mozilla wiki, what collection type of data do the requested measurements fall under?

Type 2, interaction with addons by adding one

5. Is the data collection request for default-on or default-off?

Default on

6. Does the instrumentation include the addition of any new identifiers (whether anonymous or otherwise; e.g., username, random IDs, etc. See the appendix for more details)?

No

7. Is the data collection covered by the existing Firefox privacy notice?

Yes

8. Does there need to be a check-in in the future to determine whether to renew the data? (Yes/No) (If yes, set a todo reminder or file a bug if appropriate)**

Yes, @liuche will schedule an MMA checkin with @cbonacuse for 6mo from now

9. Does the data collection use a third-party collection tool?

Leanplum, which is approved for this type of collection.