After "Page Shot" migration, "Info is undefined" error is displayed, if a Screenshots page is focused and the browser is restated using the "restart" command in "Developer Toolbar"

[SoftVision-CosminMuntean]

[Affected versions]:

• Nightly 55.0a1
• Sccreenshots 8.2.0

[Affected Platforms]:

• All Windows

[Prerequisites]:

• Have a Firefox version where Screenshots is not installed and create a new profile.
• Have the "Show you windows and tabs from last time" option set on "about:preferences" page in General section.
• Have Test Pilot and Page Shot installed on the created profile.

[Steps to reproduce]:

1. Open the Nightly try build with Screenshots 8.2.0 installed with the profile from prerequisites.
2. Wait until the "Page Shot" migration happens.
3. Open the "Developer Toolbar" (Shift + F2), type the "restart" command and press "Enter" key.
4. After the browser is opened, navigate to any website and save a selection.
5. Restart again the browser using the "restart" command.
6. After the browser is restarted observe the behavior.

[Expected result]:

• No errors are displayed.

[Actual results]:

• "TypeError: info is undefined" error is displayed.

[Notes]:

• I haven't managed to reproduce this issue on Mac Os.
• If no error are displayed, restart again the browser using the "restart" command in the "Developer Toolbar".
• Here is a screen recording with the issue: https://goo.gl/rN4xaA.
• Here is a screenshot with browser console errors:
  

[ianb]

The migration is a red herring here, it's just a matter of the page being loaded in session-restore, and a race condition in main.js around authentication.

[SoftVision-CosminMuntean]

I have retested this issue on the latest Nightly (Build ID: 20170607030206) build with latest Screenshots (9.0.0) version and is no longer reproducible. Marking as verified.