For #3086: Adds settings animations

[sblatz]

Pull Request checklist

• Tests: This PR includes thorough tests or an explanation of why it does not
• Screenshots: This PR includes screenshots or GIFs of the changes made or an explanation of why it does not
• Accessibility: The code in this PR follows accessibility best practices or does not include any user facing features. In addition, it includes a screenshot of a successful accessibility scan to ensure no new defects are added to the product.

After merge

• Milestone: Make sure issues finished by this pull request are added to the milestone of the version currently in development.

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[codecov-io]

Codecov Report

Merging #9187 into master will decrease coverage by 0.01%.
The diff coverage is 0.00%.

@@             Coverage Diff              @@
##             master    #9187      +/-   ##
============================================
- Coverage     19.51%   19.50%   -0.02%     
  Complexity      511      511              
============================================
  Files           329      329              
  Lines         13147    13155       +8     
  Branches       1746     1747       +1     
============================================
  Hits           2566     2566              
- Misses        10356    10364       +8     
  Partials        225      225              

Impacted Files	Coverage Δ	Complexity Δ
...ava/org/mozilla/fenix/settings/SettingsFragment.kt	0.00% <0.00%> (ø)	0.00 <0.00> (ø)

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[boek]

Looks good! Just a small nit :)

[boek]

can we use the kotlin view getter here? view?.recycler_view?.hideInitialScrollbar(lifecycleScope)

[sblatz]

Unfortunately, no. I tried this, and it doesn't work. My guess is that it's because we don't have direct access to the recycler view. This is actually one Android is generating based on the build in PreferenceFragment.