Repository: flutter
Issue: HardwareKeyboard handler does not fire events when textfield is in focus.
Labels: a: text input,framework,f: focus,has reproducible steps,P2,team-text-input,triaged-text-input,found in release: 3.27,found in release: 3.28

### Steps to reproduce

On Android `ServicesBinding.instance.keyboard.addHandler(keyboardHandler)` behaves differently on v3.24.5 vs 3.27.1
The steps are as follows (see example):

1. Without focusing the field 
2. Using the "open keyboard" button type: "1.1.1" (I'm using a bluetooth barcode scanner, a.k.a. external keyboard)
3. Type "4" in the field 
4. Lose focus of the field 
5. Click "open keyboard" again and type: "1.1.1" (I'm using a bluetooth barcode scanner, a.k.a. external keyboard)

In Flutter 3.24.5 all key events are handled correctly look at the "Expected results".
In Flutter 3.27.1, after editing the field and then using the barcode scanner, all "." characters are ignored. When using the on screen keyboard all key events are ignored.

This shouldn't be normal behavior right?

### Expected results

<details open><summary>Flutter 3.24.5 everything handled correctly even after typing a value in the TextField:</summary>

```
HardwareKeyboard initialized
 -------
 key pressed event1
 Key pressed: 1
 Not a key down event: ignore
 -------
 key pressed event.
 Key pressed: .
 Not a key down event: ignore
 -------
 key pressed event1
 Key pressed: 1
 Not a key down event: ignore
 -------
 key pressed event.
 Key pressed: .
 Not a key down event: ignore
 -------
 key pressed event1
 Key pressed: 1
 Not a key down event: ignore
 Textfield value: 4
 -------
 key pressed event1
 Key pressed: 1
 Not a key down event: ignore
 -------
 key pressed event.
 Key pressed: .
 Not a key down event: ignore
 -------
 key pressed event1
 Key pressed: 1
 Not a key down event: ignore
 -------
 key pressed event.
 Key pressed: .
 Not a key down event: ignore
 -------
 key pressed event1
 Key pressed: 1
 Not a key down event: ignore
```

</details>
Exactly the same output using the bluetooth barcode scanner.

### Actual results

<details open><summary> Logs: using the on screen keyboard</summary>

Flutter 3.27.1
Logs:
```
HardwareKeyboard initialized
-------
key pressed event1
Key pressed: 1
Not a key down event: ignore
-------
key pressed event.
Key pressed: .
Not a key down event: ignore
-------
key pressed event1
Key pressed: 1
Not a key down event: ignore
-------
key pressed event.
Key pressed: .
Not a key down event: ignore
-------
key pressed event1
Key pressed: 1
Not a key down event: ignore
Textfield value: 4
```

</details>
After typing the value in the TextField everything is ignored.

<details open><summary> Logs: using the bluetooth barcode scanner (a.k.a. external keyboard)</summary>

```
HardwareKeyboard initialized
-------
key pressed event1
Key pressed: 1
Not a key down event: ignore
-------
key pressed event.
Key pressed: .
Not a key down event: ignore
-------
key pressed event1
Key pressed: 1
Not a key down event: ignore
-------
key pressed event.
Key pressed: .
Not a key down event: ignore
-------
key pressed event1
Key pressed: 1
Not a key down event: ignore
-------
key pressed eventEnter
Key pressed: 
Not a key down event: ignore
Textfield value: 4
-------
key pressed event1
Key pressed: 1
Not a key down event: ignore
-------
key pressed event1
Key pressed: 1
Not a key down event: ignore
-------
key pressed event1
Key pressed: 1
Not a key down event: ignore
```

</details>
After typing the value in the TextField all "." characters are ignored.

### Code sample

<details open><summary>Code sample</summary>

```dart
import 'package:flutter/material.dart';
import 'package:flutter/services.dart';

void main() {
  runApp(const MainApp());
}

class MainApp extends StatefulWidget {
  const MainApp({super.key});

  @override
  State<MainApp> createState() => _MainAppState();
}

class _MainAppState extends State<MainApp> {
  @override
  initState() {
    ServicesBinding.instance.keyboard.addHandler(keyboardHandler);
    print("HardwareKeyboard initialized");
    super.initState();
  }

  bool keyboardHandler(KeyEvent event) {
    if (event is! KeyDownEvent) {
      print("Not a key down event: ignore");
      return false;
    }
    print("-------");
    print("key pressed event${event.logicalKey.keyLabel}");
    if (focusNode.hasFocus) {
      print("textfield has focus: ignore");
      return false;
    }
    if (event.character != null && event.character?.isNotEmpty == true) {
      print("Key pressed: ${event.character}");
      return true;
    }
    print("key pressed but not a character: ignore");
    return false;
  }

  @override
  dispose() {
    ServicesBinding.instance.keyboard.removeHandler(keyboardHandler);
    print("HardwareKeyboard disposed");
    super.dispose();
  }

  FocusNode focusNode = FocusNode();
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        body: Column(children: [
          const SizedBox(height: 100),
          TextField(
            focusNode: focusNode,
            onChanged: (value) {
              print("Textfield value: $value");
            },
          ),
          TextButton(
              onPressed: () {
                focusNode.unfocus();
              },
              child: const Text("unfocus")),
          TextButton(
              onPressed: () {
                SystemChannels.textInput.invokeMethod("TextInput.show");
              },
              child: const Text("Open keyboard")),
        ]),
      ),
    );
  }
}
```

</details>


### Screenshots or Video

_No response_

### Logs

_No response_

### Flutter Doctor output

<details open><summary>Doctor output 3.27.1</summary>

```console
Doctor summary (to see all details, run flutter doctor -v):
[√] Flutter (Channel stable, 3.27.1, on Microsoft Windows [Version 10.0.22631.4602], locale en-NL)
[√] Windows Version (Installed version of Windows is version 10 or higher)
[√] Android toolchain - develop for Android devices (Android SDK version 35.0.0)
[√] Chrome - develop for the web
[√] Visual Studio - develop Windows apps (Visual Studio Community 2022 17.11.6)
[!] Android Studio (version 2022.1)
    X Unable to determine bundled Java version.
[!] Android Studio (version 2023.3)
    X Unable to determine bundled Java version.
[√] Android Studio (version 2024.2)
[√] VS Code (version 1.94.2)
[√] VS Code, 64-bit edition (version unknown)
    X Unable to determine VS Code version.
[√] Connected device (4 available)
[√] Network resources
```

</details>
<details open><summary>Doctor output 3.24.5</summary>

```console
Doctor summary (to see all details, run flutter doctor -v):
[√] Flutter (Channel stable, 3.24.5, on Microsoft Windows [Version 10.0.22631.4602], locale en-NL)
[√] Windows Version (Installed version of Windows is version 10 or higher)
[√] Android toolchain - develop for Android devices (Android SDK version 35.0.0)
[√] Chrome - develop for the web
[√] Visual Studio - develop Windows apps (Visual Studio Community 2022 17.11.6)
[!] Android Studio (version 2022.1)
    X Unable to determine bundled Java version.
[!] Android Studio (version 2023.3)
    X Unable to determine bundled Java version.
[√] Android Studio (version 2024.2)
[√] VS Code (version 1.94.2)
[√] VS Code, 64-bit edition (version unknown)
    X Unable to determine VS Code version.
[√] Connected device (4 available)
[√] Network resources
```

</details>