Sync Android AccessibilityFeature enum and dart:ui

[cbracken]

This brings the Android accessibility bridge AccessibilityFeature enum
back in sync with the AccessibilityFeatures class in dart:ui, defined
in lib/ui/window.dart

Keeping these enums in sync aids in automated API consistency checking.

Issue: flutter/flutter#101217

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• I read the Contributor Guide and followed the process outlined there for submitting PRs.
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• I listed at least one issue that this PR fixes in the description above.
• I added new tests to check the change I am making or feature I am adding, or Hixie said the PR is test-exempt. See testing the engine for instructions on
  writing and running engine tests.
• I updated/added relevant documentation (doc comments with ///).
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[flutter-dashboard]

It looks like this pull request may not have tests. Please make sure to add tests before merging. If you need an exemption to this rule, contact Hixie on the #hackers channel in Chat (don't just cc him here, he won't see it! He's on Discord!).

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[cbracken]

Tests to ensure enums remain in sync between dart:ui and the various platforms are added in #32408.

[chunhtai]

LGTM,

It will be good if we have some sort of test to ensure this...

[cbracken]

It will be good if we have some sort of test to ensure this...

See #32408