Repository: flutter
Issue: Touchscreen enabled desktop devices do not register a PointerDeviceKind.touch
Labels: framework,f: scrolling,a: desktop,P2,team-framework,triaged-framework

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Touchscreen scrolling on Linux Desktop no longer working since Flutter 2.5. I assume this came because the "mouse-hold-scrolling" has been removed but this also breaks the touchscreen input completely. This is very unfortunately because this makes my app (and all other Flutter apps) unusable on the Pinephone, the Librem 5 and other Linux phones, where I already had a lot of users who now all are going to uninstall my app :-(((

## Steps to Reproduce
1. Build an app for Linux Desktop
2. Try to scroll with the touchscreen

<!-- You must include full steps to reproduce so that we can reproduce the problem. -->


**Expected results:** 
Touchscreen works like before.

**Actual results:**
Touchscreen input no longer works.

<details>
  <summary>Logs</summary>

<!-- Finally, paste the output of running `flutter doctor -v` here. -->

```
[✓] Flutter (Channel stable, 2.5.1, on Ubuntu 20.04.3 LTS 5.11.0-34-generic, locale de_DE.UTF-8)
    • Flutter version 2.5.1 at /home/krille/Applications/flutter
    • Upstream repository https://github.com/flutter/flutter.git
    • Framework revision ffb2ecea52 (vor 2 Tagen), 2021-09-17 15:26:33 -0400
    • Engine revision b3af521a05
    • Dart version 2.14.2

[✓] Android toolchain - develop for Android devices (Android SDK version 31.0.0-rc5)
    • Android SDK at /home/krille/Android/Sdk
    • Platform android-31, build-tools 31.0.0-rc5
    • Java binary at: /snap/android-studio/114/android-studio/jre/bin/java
    • Java version OpenJDK Runtime Environment (build 11.0.10+0-b96-7249189)
    • All Android licenses accepted.

[✓] Chrome - develop for the web
    • Chrome at google-chrome

[✗] Linux toolchain - develop for Linux desktop
    • clang version 10.0.0-4ubuntu1
    • cmake version 3.16.3
    • ninja version 1.10.0
    • pkg-config version 0.29.2
    ✗ GTK 3.0 development libraries are required for Linux development.
      They are likely available from your distribution (e.g.: apt install libgtk-3-dev)

[✓] Android Studio (version 2020.3)
    • Android Studio at /snap/android-studio/114/android-studio
    • 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 11.0.10+0-b96-7249189)

[✓] VS Code
    • VS Code at /snap/code/current
    • Flutter extension version 3.26.0

[✓] Connected device (2 available)
    • Linux (desktop) • linux  • linux-x64      • Ubuntu 20.04.3 LTS 5.11.0-34-generic
    • Chrome (web)    • chrome • web-javascript • Google Chrome 91.0.4472.114
```

</details>