Custom non-blocking js alert

[mallexxx]

Task/Issue URL: https://app.asana.com/0/715106103902962/1202323846903922/f Tech Design URL: CC: @miasma13

Description: Custom JS alert non-blocking browser interface an allowing to close the tab https://www.figma.com/file/HZjSfXLUCIcTfDLFJAkM7h/JS-alerts?node-id=709%3A2601

• Requires product review

Steps to test this PR:

1. Validate alert/prompt/confirm js commands are working and returning valid result (https://w3cschools/jsref/met_win_alert.asp could be used for testing)
2. Validate tab can be closed and the browser UI is not blocked

Orientation Testing:

• [ ] Portrait
• [ ] Landscape

Device Testing:

• [ ] iPhone SE (1st Gen)
• [ ] iPhone X
• [ ] iPad

Theme Testing:

• [ ] Light theme
• [ ] Dark theme

---

Internal references:

Software Engineering Expectations Technical Design Template When ready for review, remember to post the PR in MM

[Bunn]

@mallexxx while testing on my iPhone 13 mini - iOS 15.5 I can't manage to see the custom alerts. It seems they are presented there, but the x/y position is wrong. You can see when I rotate the device it flashes for a split second.

https://user-images.githubusercontent.com/782316/179976888-5a0ca041-92c2-405d-bf01-ed0c06218c32.MP4

[Bunn]

@mallexxx I'm assigning this back to you, please assign it back to me once it's ready for review again. Thanks

[mallexxx]

Thanks @Bunn, this should be ready for review now

[mallexxx]

Thanks once again :) Done