Color picker breaks hot reload

## Steps to Reproduce

Use the color picker.

https://user-images.githubusercontent.com/58381615/136134003-c765a8a6-d809-428a-a4fb-c903b982afcb.mp4

## Version info

```
[✓] Flutter (Channel stable, 2.5.2, on Microsoft Windows [Version 10.0.19043.1202], locale en-US)
• Flutter version 2.5.2 at C:\Users\fctor\Desktop\flutter
• Upstream repository https://github.com/flutter/flutter.git
• Framework revision 3595343e20 (5 days ago), 2021-09-30 12:58:18 -0700
• Engine revision 6ac856380f
• Dart version 2.14.3

[✓] Android toolchain - develop for Android devices (Android SDK version 30.0.3)
• Android SDK at C:\Users\fctor\AppData\Local\Android\sdk
• Platform android-30, build-tools 30.0.3
• Java binary at: C:\Program Files\JetBrains\IntelliJ IDEA 2021.1.3\jbr\bin\java
• Java version OpenJDK Runtime Environment JBR-11.0.12.7-1504.28-jcef (build 11.0.12+7-b1504.28)
• All Android licenses accepted.

[✓] Chrome - develop for the web
• Chrome at C:\Program Files\Google\Chrome\Application\chrome.exe

[✓] Visual Studio - develop for Windows (Visual Studio Community 2019 16.11.1)
• Visual Studio at C:\Program Files (x86)\Microsoft Visual Studio\2019\Community
• Visual Studio Community 2019 version 16.11.31613.86
• Windows 10 SDK version 10.0.19041.0

[!] Android Studio (not installed)
• Android Studio not found; download from https://developer.android.com/studio/index.html
(or visit https://flutter.dev/docs/get-started/install/windows#android-setup for detailed instructions).

[✓] IntelliJ IDEA Ultimate Edition (version 2021.2)
• IntelliJ at C:\Program Files\JetBrains\IntelliJ IDEA 2021.1.3
• Flutter plugin version 60.1.4
• Dart plugin version 212.5486

[✓] VS Code (version 1.60.2)
• VS Code at C:\Users\fctor\AppData\Local\Programs\Microsoft VS Code
• Flutter extension version 3.26.0

[✓] Connected device (3 available)
• Windows (desktop) • windows • windows-x64 • Microsoft Windows [Version 10.0.19043.1202]
• Chrome (web) • chrome • web-javascript • Google Chrome 94.0.4606.61
• Edge (web) • edge • web-javascript • Microsoft Edge 92.0.902.78

! Doctor found issues in 1 category.
```