Repository: flutter
Issue: Raw web keyCode cannot be extracted from KeyEvent
Labels: a: text input,e: device-specific,platform-web,P2,team-web,triaged-web

### Description

We have migrated our keyboard handling from Flutter 3.16 to 3.19 according to [this migration guide](https://docs.flutter.dev/release/breaking-changes/key-event-migration#migrating-your-code-that-uses-rawkeyevent). After the migration we can't get the keyCode from the KeyEvent as we did before.
We're using Flutter for a webos application and for that we need to get the keyCode from the `RawKeyEventDataWeb` to distinguish between the special keys coming from the [LG magic remote](https://webostv.developer.lge.com/develop/guides/magic-remote).

### Expected results

KeyCode like 413 for stop

### Actual results

We're getting the `usbHidUsage`: `0x01700000000` and the `LogicalKeyboardKey` `unidentified`

### Code sample

<details open><summary>Code sample</summary>

```dart
Focus(
      onKeyEvent: (FocusNode node, KeyEvent event) {
        if (event is RawKeyDownEvent && event.data is RawKeyEventDataWeb) {
          final keyCode = (event.data as RawKeyEventDataWeb).keyCode;
          // Do something with the key code
        }
        return KeyEventResult.ignored;
      },
      child: ...

```

</details>


### Flutter Doctor output

<details open><summary>Doctor output</summary>

```console
[✓] Flutter (Channel stable, 3.19.6, on macOS 14.4.1 23E224 darwin-arm64, locale de-DE)
    • Flutter version 3.19.6 on channel stable at ...
    • Upstream repository https://github.com/flutter/flutter.git
    • Framework revision 54e66469a9 (5 days ago), 2024-04-17 13:08:03 -0700
    • Engine revision c4cd48e186
    • Dart version 3.3.4
    • DevTools version 2.31.1

[✓] Android toolchain - develop for Android devices (Android SDK version 34.0.0)
    • Android SDK at ...
    • Platform android-34, build-tools 34.0.0
    • Java binary at: /Applications/Android Studio.app/Contents/jbr/Contents/Home/bin/java
    • Java version OpenJDK Runtime Environment (build 17.0.9+0-17.0.9b1087.7-11185874)
    • All Android licenses accepted.

[✓] Xcode - develop for iOS and macOS (Xcode 15.0)
    • Xcode at /Applications/Xcode.app/Contents/Developer
    • Build 15A240d
    • CocoaPods version 1.15.2

[✓] Chrome - develop for the web
    • Chrome at /Applications/Google Chrome.app/Contents/MacOS/Google Chrome

[✓] Android Studio (version 2023.2)
    • Android Studio at /Applications/Android Studio.app/Contents
    • Flutter plugin can be installed from:
      🔨 https://plugins.jetbrains.com/plugin/9212-flutter
    • Dart plugin can be installed from:
      🔨 https://plugins.jetbrains.com/plugin/6351-dart
    • Java version OpenJDK Runtime Environment (build 17.0.9+0-17.0.9b1087.7-11185874)

[✓] Android Studio (version 2023.1)
    • Android Studio at /Applications/Android Studio2.app/Contents
    • Flutter plugin can be installed from:
      🔨 https://plugins.jetbrains.com/plugin/9212-flutter
    • Dart plugin can be installed from:
      🔨 https://plugins.jetbrains.com/plugin/6351-dart
    • Java version OpenJDK Runtime Environment (build 17.0.7+0-17.0.7b1000.6-10550314)

[✓] VS Code (version 1.88.1)
    • VS Code at /Applications/Visual Studio Code.app/Contents
    • Flutter extension can be installed from:
      🔨 https://marketplace.visualstudio.com/items?itemName=Dart-Code.flutter

[✓] Connected device (2 available)
    • macOS (desktop) • macos  • darwin-arm64   • macOS 14.4.1 23E224 darwin-arm64
    • Chrome (web)    • chrome • web-javascript • Google Chrome 124.0.6367.62

[✓] Network resources
    • All expected network resources are available.

• No issues found!

```

</details>