Add handling of app links

[joshliebe]

Task/Issue URL: https://app.asana.com/0/72649045549333/1199533149091655/f
Tech Design URL: https://app.asana.com/0/481882893211075/1200311072033594
CC:

Description:
This PR adds handling of App Links.

When a user taps an app link they will be prompted to open the link in the corresponding app (By tapping the "Yes" button) or view the content in the browser (By tapping the "No" button"). If there are multiple apps that can handle the link, then a chooser is shown.

The feature can be enabled/disabled in settings. It is enabled by default.

Screenshots:

Dialog	Chooser	Setting

Steps to test this PR:

1. Search for "Google Maps".
2. Tap the first link.
3. Select "Yes" from the dialog and it should navigate to the Google Maps app.
4. Go back and tap the link again and select "No" from the dialog. It should open the link in the browser.
5. Go to settings, disable "Open Links in Associated Apps".
6. Tap the link again and verify that the dialog does not show and that link is opened in the browser.
7. Enable the setting again.
8. Install multiple apps that can handle a link: Twitter and Twitter Lite.
9. Search for "Twitter DuckDuckGo".
10. Tap the first link and choose "Yes" from the dialog.
11. Verify that the chooser is shown with associated apps.
12. Type in a URL associated with an app, such as maps.google.com. Verify that the link is navigated to in the browser.

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Internal references:

Software Engineering Expectations
Technical Design Template

[malmstein]

Good job @joshliebe. Left a few comments but feel free to ignore what you don't agree with.

[joshliebe]

Good job @joshliebe. Left a few comments but feel free to ignore what you don't agree with.

Thanks for reviewing @malmstein, will address the comments 👍

[cmonfortep]

Thanks @joshliebe. This looks great, I left some minor comments, feel free to skip them.

I've tested this on my device and it works as described 👍

[cmonfortep]

I've noticed handleAppLink and handleNonHttpAppLink both return Boolean, but the same boolean can have different meanings. E.g: here when NonHttpAppLink not handled we return true, but in handleAppLink we return false.

is there any specific reason why return true in this case?

[joshliebe]

For non-HTTP links, like market:// or intent://, true is returned so that they are ignored. If false is returned for those links, they will open in the browser and the user will see the WebView error page because they can't be handled. false is returned for HTTP app links since the WebView can open those.

[joshliebe]

Thanks for reviewing @cmonfortep 🙂