Make sure that cookies are saved to disk when closing the app

[yuya-oc]

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Summary
Make sure that cookies are saved to disk when closing the app.

Somehow cookies are not immediately saved to disk. Possibly electron/electron#8416 is related.
So I manually called cookies.flushStore() when the app is quitting or the window loses focus. This would cover almost use cases even if application crashed.

Issue link
Original report: https://pre-release.mattermost.com/core/pl/m4s6qfjb5f815x4co388pscrfe

Test Cases

1. Quit the app.
2. Remove the application data folder
   • Windows: AppData\Roaming\Mattermost
   • Mac: ~/Library/Application Support/Mattermost
   • Linux: ~/.config/Mattermost
3. Open the app.
4. Login to webapp then quit the app soon (Ctrl/Cmd+Q shortcut).
5. Reopen the app.
6. You should not be logged out from webapp.

Additional Notes

[amyblais]

@yuya-oc What is the testing server for this?

[yuya-oc]

It would be available at https://circleci.com/gh/yuya-oc/desktop/825#artifacts. CircleCI was delaying.

[yuya-oc]

Tested on Ubuntu 16.04. Now login session is persisted.

[amyblais]

@yuya-oc Works well, just one question about the expected: when I remove the application data folder (step 2) and then reopen the app (step 3), all my servers have disappeared and the "Add Server" page shows up when I reopen the app - this is expected?

[jasonblais]

Looks good for me too

[jasonblais]

@amyblais It is - that folder contains your users config.json file, which contains all the app settings and servers you configured. Since you deleted it, they were all wiped out..