Hi !
I'm currently building a RichTextField/RichTextEditor for Flutter, but I started having some bugs on MacOS that I don't have on other platforms (iOS, Web, Android). I wondered what it was and found out that the backspace key triggers the "onChanged" method multiple times on MacOS (might be the same on Windows or Linux, I don't have access to any of these OS to try, so I don't know).

Steps to Reproduce

1. Run flutter create bug.
2. In main.dart : inside the build method of _MyHomePageState, remove everything inside "body" and replace it with this :

TextField(
        onChanged: (text) => print('textChanged'),
      ),

3. Run on macOS.
4. Write some text (even a single letter would work).
5. (Optional) Clear the log console.
6. Press backspace once.

Expected results: "textChanged" logged 1x in the console.

Actual results: "textChanged" logged 3x in the console.