Description

The arrow key event has the error cursor position when the text is selected.
example: #58068

@justinmc @gspencergoog

Related Issues

#58068

Tests

I added the following tests:

• editable_test.dart
  • arrow keys with selection text

Replace this with a list of the tests that you added as part of this PR. A change in behavior with no test covering it
will likely get reverted accidentally sooner or later. PRs must include tests for all changed/updated/fixed behaviors. See Test Coverage.

Checklist

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• I read the Contributor Guide and followed the process outlined there for submitting PRs.
• I signed the CLA.
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• I read the Tree Hygiene wiki page, which explains my responsibilities.
• I updated/added relevant documentation (doc comments with ///).
• All existing and new tests are passing.
• The analyzer (flutter analyze --flutter-repo) does not report any problems on my PR.
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Breaking Change

Did any tests fail when you ran them? Please read Handling breaking changes.

• No, no existing tests failed, so this is not a breaking change.
• Yes, this is a breaking change. If not, delete the remainder of this section.
  • I wrote a design doc: https://flutter.dev/go/template Replace this with a link to your design doc's short link
  • I got input from the developer relations team, specifically from: Replace with the names of who gave advice
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Some of the original tests were unreasonable expectations, so I revised the tests.