defer loading until after any clear event

[brindy]

Task/Issue URL: https://app.asana.com/0/414709148257752/1206454582708636/f
Tech Design URL:
CC:

Description:
Defers launching a URL until data clearing has finished.

Steps to test this PR:

1. Visit setcookie.net and set a cookie (favourite this page for speed)
2. Check the fire button works as expected (cookie is cleared, fireproofing works)
3. With browser set as default, launch a URL - should load correctly without any tabs closed or data cleared
4. Remove any fireproofing for the setcookie.net
5. Set a new cookie
6. Enable autoclear and kill the app
7. Launch a URL - page should load
8. Check setcookie.net has no cookies and all tabs were closed

General smoke testing:

1. Browse several websites
2. Set cookies with https://www.setcookie.net
3. Use the fire button and ensure data is cleared and app is ready to search again

[brindy]

rebasing against the release