For #11479: Record open tabs count in metrics ping

[sblatz]

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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[sblatz]

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?

• How many tabs do users keep open?

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?

• We need to know how many tabs users keep open average so we can make decisions about optomizations around features like tabs tray (is this system sufficient for seeing large lists, etc.).

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

• We do not have telemetry to track open tabs. Total URI only tracks sessions but they could all be within the same tab.

4. Can current instrumentation answer these questions?

• No, see above.

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?

• Until 09/01/2020

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.

• Glean / Amplitude

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

• Only on Glean, Amplitude and with mobile teams.

[eliserichards]

Let's get this bread tab count 💯

[liuche]

data-review+

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?

Documented tab count in docs/metrics.md

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

Yes, fenix telemetry controls

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

Has expiry of 9/2020

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, user usage data of tabs

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)**

No, has expiry

9. Does the data collection use a third-party collection tool? If yes, escalate to legal.

No

[darkwing]

Looks good to me!