Fixes #9832 - Change targetSdkVersion to Android 10

[NotWoods]

No major changes to upgrade now!

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.

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• 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-commenter]

Codecov Report

Merging #11014 into master will decrease coverage by 13.30%.
The diff coverage is 14.28%.

@@              Coverage Diff              @@
##             master   #11014       +/-   ##
=============================================
- Coverage     22.12%    8.82%   -13.31%     
+ Complexity      725      245      -480     
=============================================
  Files           377      373        -4     
  Lines         15098    15040       -58     
  Branches       1957     2032       +75     
=============================================
- Hits           3341     1327     -2014     
- Misses        11469    13619     +2150     
+ Partials        288       94      -194     

Impacted Files	Coverage Δ	Complexity Δ
...ozilla/fenix/library/bookmarks/BookmarkFragment.kt	0.00% <0.00%> (ø)	0.00 <0.00> (ø)
...mozilla/fenix/library/history/HistoryController.kt	3.84% <0.00%> (-96.16%)	0.00 <0.00> (ø)
...a/fenix/settings/logins/SavedLoginsAuthFragment.kt	0.00% <0.00%> (ø)	0.00 <0.00> (ø)
...n/java/org/mozilla/fenix/utils/ClipboardHandler.kt	0.00% <0.00%> (-73.34%)	0.00 <0.00> (-14.00)
...java/org/mozilla/fenix/whatsnew/WhatsNewStorage.kt	0.00% <ø> (-94.12%)	0.00 <0.00> (ø)
...illa/fenix/library/bookmarks/BookmarkController.kt	95.83% <50.00%> (-4.17%)	0.00 <0.00> (ø)
...pp/src/main/java/org/mozilla/fenix/ext/Activity.kt	0.00% <0.00%> (-100.00%)	0.00% <0.00%> (ø%)
...pp/src/main/java/org/mozilla/fenix/ext/Drawable.kt	0.00% <0.00%> (-100.00%)	0.00% <0.00%> (ø%)
...src/main/java/org/mozilla/fenix/ext/ImageButton.kt	0.00% <0.00%> (-100.00%)	0.00% <0.00%> (ø%)
...rc/main/java/org/mozilla/fenix/GlobalDirections.kt	0.00% <0.00%> (-100.00%)	0.00% <0.00%> (-2.00%)
... and 162 more

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[jonalmeida]

This looks good to me now that we've cut a release.

[jonalmeida]

I don't think we should use un-safe calls if the newer target SDK asserts them as nullable. Some devices maybe not support some system services and we shouldn't crash because of that.

[NotWoods]

We're already using unsafe calls as we cast nullable to not-null. The SDK doesn't assert if a system service is null or not, the extension method simply always returns a nullable type.

[jonalmeida]

Same as the previous comment.