Towards #172014.

Cherrypick's #172236 into the 3.35 release branch _and_ tests it live by setting `engine.version` in this PR.

… for some silly reason (#172263)

This pull request is created by [automatic cherry pick workflow](https://github.com/flutter/flutter/blob/main/docs/releases/Flutter-Cherrypick-Process.md#automatically-creates-a-cherry-pick-request)
Please fill in the form below, and a flutter domain expert will evaluate this cherry pick request.

### Issue Link:
What is the link to the issue this cherry-pick is addressing?

#172257

### Changelog Description:
Explain this cherry pick in one line that is accessible to most Flutter developers. See [best practices](https://github.com/flutter/flutter/blob/main/docs/releases/Hotfix-Documentation-Best-Practices.md) for examples

N/A

### Impact Description:
What is the impact (ex. visual jank on Samsung phones, app crash, cannot ship an iOS app)? Does it impact development (ex. flutter doctor crashes when Android Studio is installed), or the shipping production app (the app crashes on launch)

Cannot release (Windows builder fails)

### Workaround:
Is there a workaround for this issue?

No

### Risk:
What is the risk level of this cherry-pick?

### Test Coverage:
Are you confident that your fix is well-tested by automated tests?

### Validation Steps:
What are the steps to validate that this fix works?

Try publishing another release

to use, correctly, 1c9c20e.

This pull request is created by [automatic cherry pick workflow](https://github.com/flutter/flutter/blob/main/docs/releases/Flutter-Cherrypick-Process.md#automatically-creates-a-cherry-pick-request)
Please fill in the form below, and a flutter domain expert will evaluate this cherry pick request.

### Issue Link:
What is the link to the issue this cherry-pick is addressing?

#57497

### Changelog Description:
Explain this cherry pick in one line that is accessible to most Flutter developers. See [best practices](https://github.com/flutter/flutter/blob/main/docs/releases/Hotfix-Documentation-Best-Practices.md) for examples

N/A (Beta)

### Impact Description:
What is the impact (ex. visual jank on Samsung phones, app crash, cannot ship an iOS app)? Does it impact development (ex. flutter doctor crashes when Android Studio is installed), or the shipping production app (the app crashes on launch)

Provides a CLI-issued warning to plugins using a workaround we wanted to remove in 2020.

Once this is CP'd in 3.35, the `master` branch (post-3.35) can remove the workaround/tech debt.

### Workaround:
Is there a workaround for this issue?

N/A

### Risk:
What is the risk level of this cherry-pick?

### Test Coverage:
Are you confident that your fix is well-tested by automated tests?

### Validation Steps:
What are the steps to validate that this fix works?

N/A

…ction.cancel (#172675)

This pull request is created by [automatic cherry pick workflow](https://github.com/flutter/flutter/blob/main/docs/releases/Flutter-Cherrypick-Process.md#automatically-creates-a-cherry-pick-request)
Please fill in the form below, and a flutter domain expert will evaluate this cherry pick request.

### Issue Link:
What is the link to the issue this cherry-pick is addressing?

#172250

### Changelog Description:
Explain this cherry pick in one line that is accessible to most Flutter developers. See [best practices](https://github.com/flutter/flutter/blob/main/docs/releases/Hotfix-Documentation-Best-Practices.md) for examples

Fixes a bug where `TextInput.hide` call incorrect clears the text in the active text field.

### Impact Description:
What is the impact (ex. visual jank on Samsung phones, app crash, cannot ship an iOS app)? Does it impact development (ex. flutter doctor crashes when Android Studio is installed), or the shipping production app (the app crashes on launch)

If an app calls `TextInput.hide` to hide the software keyboard, the user input in the current active text field will also be erased. It impacts the production app.
The framework itself doesn't seem to call `TextInput.hide` in a way that would affect the user.

### Workaround:
Is there a workaround for this issue?

Yes, in theory, developers can store and restore the `TextEditingValue`, when they need to call `TextInput.hide`, to undo the clear. However I suspect the reverted PR may also [break voiceover](#145681 (comment)).

### Risk:
What is the risk level of this cherry-pick?

This is a revert of #160653. The reverted PR was merged in February, and the previous implementation was [introduced in 2021](flutter/engine#23776).

### Test Coverage:
Are you confident that your fix is well-tested by automated tests?

  - [] No

This change is a revert so the added test will also get reverted.

### Validation Steps:
What are the steps to validate that this fix works?

To verify the fix on master (it has already landed on master), run this app:
```dart
import 'package:flutter/material.dart';
import 'package:flutter/services.dart';

void main() {
  runApp(const MyApp());
}

class MyApp extends StatelessWidget {
  const MyApp({super.key});

  @OverRide
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      debugShowCheckedModeBanner: false,
      theme: ThemeData(
        colorScheme: ColorScheme.fromSeed(seedColor: Colors.deepPurple),
        useMaterial3: true,
      ),
      home: const MyHomePage(),
    );
  }
}

class MyHomePage extends StatelessWidget {
  const MyHomePage({super.key});

  @OverRide
  Widget build(BuildContext context) {
    return Scaffold(
      body: Center(
        child: SizedBox(
          child: ListView(
            children: [
              TextButton(
                child: Text('hide keyboard'),
                onPressed: () =>
                    SystemChannels.textInput.invokeListMethod("TextInput.hide"),
              ),
              TextField(
                controller: TextEditingController(text: '️a' * 20),
                maxLines: 1,
              ),
            ],
          ),
        ),
      ),
    );
  }
}
```
focus the text field and then click the hide keyboard button. The text "aaaaaa..." should remain after the button is clicked.

…uage tag (#172711)

This pull request is created by [automatic cherry pick workflow](https://github.com/flutter/flutter/blob/main/docs/releases/Flutter-Cherrypick-Process.md#automatically-creates-a-cherry-pick-request)
Please fill in the form below, and a flutter domain expert will evaluate this cherry pick request.

### Issue Link:
What is the link to the issue this cherry-pick is addressing?

#162324

### Changelog Description:
Explain this cherry pick in one line that is accessible to most Flutter developers. See [best practices](https://github.com/flutter/flutter/blob/main/docs/releases/Hotfix-Documentation-Best-Practices.md) for examples

This PR fixes a bug where the locale property of a Text widget was not being correctly passed to the accessibility layer, resulting in screen readers not knowing the language of the text.

### Impact Description:
What is the impact (ex. visual jank on Samsung phones, app crash, cannot ship an iOS app)? Does it impact development (ex. flutter doctor crashes when Android Studio is installed), or the shipping production app (the app crashes on launch)

This bug critically impacted accessibility, causing screen readers to mispronounce text in foreign languages and creating a confusing, inaccessible experience for users with visual impairments. The fix ensures the locale property on the Text widget is no longer ignored, correctly passing the language information to the underlying accessibility services so the text is read intelligibly.

### Workaround:
Is there a workaround for this issue?

No.

### Risk:
What is the risk level of this cherry-pick?

### Test Coverage:
Are you confident that your fix is well-tested by automated tests?

### Validation Steps:
What are the steps to validate that this fix works?

Unit tests verify this change works as expected.