during user uninstall, isn't firing survey

[gregglind]

To Repro:

1. in a study (such as example/small-study), the user about:addons and user-disables the addon.

What does happen:

1. OK: Telemetry (for user-disable, and exit is sent
2. NOT OK: the onEndStudy signal is NOT received.

Implications:

1. If we want to open surveys for 'user-disable', we have to do it at the 'Dangerous' layer, and not at the 'webExtension' layer.

Possible Causes

1. getApi is no longer available.

What next?

1. Option 1: Use Services.wm to FORCE OPEN a tab for the survey.

• this is different than other behaviour, where the webExt does that tab opening work, OPTIONALLY. It requires documentation to explain this, and how it's weird.
• it's hard to test.

2. Option 2: Accept it as is. Benefits: no weird coding.
3. Option 3: (Preferred, Pie in the sky). Make it that addon uninstalls come with a 'reason' code.

A curveball

• when normandy uninstalls a shield addon, it looks like a user-disable
• this means that if a normandy 'revoke' happens (for example, an addon bug), EVERYONE will get surveyed, as though they uninstalled it.
• therefore, as a pattern, should we just 'ignore' surveying during 'user-disable'.

GL

[aswan]

Do you just want to open a particular url when the extension is uninstalled?
There's an API for that:
https://developer.mozilla.org/en-US/Add-ons/WebExtensions/API/runtime/setUninstallURL

[motin]

@aswan That is possible a good API to cover the case of a debrief survey specifically for add-on-installation, but as long as when normandy uninstalls a shield add-on, it looks like a user-disable, we can't use it without risking survey URLs opening in the wrong situation. Also, we need to have a way to add ending-specific metadata to the URL in order to show the corresponding debrief survey.

[gregglind]

This will be solved by #246 once implemented.