Focus-android: Consider implementing long press on back button to open back stack

[mcomella]

Why/User Benefit/User Problem

Sometimes a user wants to go back in history by more than one site: this requires them to hit the back button until the page they wanted to see has been loaded. However, wobile devices can be slow and have limited bandwidth so this process can take a while and unnecessarily cost them money reloading undesired page resources.

Fennec has a feature where you can long-press the back button to open the back stack: it'd be cool to implement something similar. Here's what fennec's looks like:

See https://github.com/mozilla-mobile/android-components/issues/1275 for how we might share this code in components and https://github.com/mozilla-mobile/firefox-tv/issues/1465 for the Fire TV feature request.

@aminalhazwani What do you think of this idea?

What / Requirements

• Implement back stack for feature: get back stack information from components and maybe wrap more things in components
• Implement front-end: optional components help here (e.g. an adapter they can implement)

Acceptance Criteria (how do I know when I’m done?)

[mcomella]

We'll discuss in the Fire TV issue: https://github.com/mozilla-mobile/firefox-tv/issues/1465#issuecomment-436178447

[Poopooracoocoo]

This would be so great! Especially for sites that manipulate history like Outlook! I can never escape Outlook.

[mathu97]

Can I take this please?

[Poopooracoocoo]

@mathu97 please do! Development on Focus is rather stagnant, probably because they're working on Fenix

[mcomella]

@mathu97 Unfortunately, I don't believe we're actively reviewing pull requests on focus right now so I'd suggest not taking this issue if your goal is to merge the code into master – Poopooracoocoo is correct in that we're focusing on Fenix right now. I'll note there are many contribution opportunities there.