Clear cache and cookies when uninstalling a WebApp

[Peter Bittner]

When a WebApp is uninstalled both cache and cookies should be removed to ensure a new installation will start from a clean state.

- Cache: $ rm -r /home/phablet/.cache/<name-of-app>
- Cookies: $ rm -r /home/phablet/.local/share/<name-of-app>

This issue has been discussed in "How clear cache and cookies of WebApp? (Gmail WebApp)" on the ubuntu-phone mailing list. A possible negative side-effect of *not* clearing cookies and cache is described in the thread.

- https://lists.launchpad.net/ubuntu-phone/msg14910.html
- https://lists.launchpad.net/ubuntu-phone/msg14861.html

[Peter Bittner (peter-bittner)]

A more elaborate approach to address this problem is described at https://lists.launchpad.net/ubuntu-phone/msg14910.html

- When you try to uninstall an app, and you click on the [ Uninstall ] button in Applications, you're taken to a confirmation screen.
- On this confirmation screen place a checkbox (or the like) below the [ Confirm ] button, labelled "Remove application data", unchecked by default.
- There could be some additional small print explaining what this is all about, either immediately or as soon as the checkbox is being checked (preferred). There's plenty space on the confirmation page. At least on the Aquaris E5.
- (In addition, I feel the [ Confirm ] button should say [ Uninstall ] to make it more explicit what's going to happen.)

I know this additional choice clutters the confirmation page a bit, but ... it's for a good purpose.

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.