Use global navigation action for browser fragment

[NotWoods]

Global actions are meant to let multiple fragments navigate to the name destination. We can use the global browser fragment action for all browser fragment navigation and get rid of the complex switch case.

Builds towards separate custom tab fragment and PWA support.

Pull Request checklist

• Quality: This PR builds and passes detekt/ktlint checks (A pre-push hook is recommended)
• Tests: This PR includes thorough tests or an explanation of why it does not
• Changelog: This PR includes a changelog entry or does not need one
• Accessibility: The code in this PR follows accessibility best practices or does not include any user facing features

[codecov-io]

Codecov Report

Merging #4691 into master will increase coverage by 0.09%.
The diff coverage is 80%.

@@             Coverage Diff             @@
##             master   #4691      +/-   ##
===========================================
+ Coverage      6.69%   6.79%   +0.09%     
- Complexity      152     154       +2     
===========================================
  Files           203     204       +1     
  Lines          8494    8480      -14     
  Branches       1189    1189              
===========================================
+ Hits            569     576       +7     
+ Misses         7886    7865      -21     
  Partials         39      39

Impacted Files	Coverage Δ	Complexity Δ
...pp/src/main/java/org/mozilla/fenix/HomeActivity.kt	1.91% <0%> (+0.23%)	3 <0> (ø)	⬇️
...rc/main/java/org/mozilla/fenix/BrowserDirection.kt	100% <100%> (ø)	2 <2> (?)
app/src/main/java/org/mozilla/fenix/ext/Context.kt	16% <0%> (-4%)	0% <0%> (ø)

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[colintheshots]

Thanks for the change. I'm fairly sure Proguard/R8 doesn't know what to do with a Nullable enum, so it will go unoptimized. This is a minor gripe, sure, but it would be best to use only int primitives.

[ekager]

I'm going to revert this. Since all of our browser navgiations go through HomeActivity we need to be careful about changing things there. Every action in the nav graph has it's own popTo, anim, etc defined in the nav graph. By using global for every action to the browser, we are breaking those.

[NotWoods]

Sounds good, I'll explore other options for custom tabs fragment.