Repository: flutter
Issue: Flutter PageView scroll animation lag/pause with CameraPreview widget
Labels: p: camera,package,team-ecosystem,has reproducible steps,P2,found in release: 2.2,found in release: 2.5,triaged-ecosystem

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When using PageView, if I have a camera preview widget as the second page, when scrolling to that page there seems to be a pause/stutter during the scroll animation, it seems to be related to the camera initialze() method.
The issue has also been reported here with a simplified code sample.
https://stackoverflow.com/questions/51171155/flutter-camera-frame-drops-when-switching-between-pages

<!-- You must include full steps to reproduce so that we can reproduce the problem. -->

Can be reproduced with code from this post.
https://stackoverflow.com/questions/51171155/flutter-camera-frame-drops-when-switching-between-pages

**Expected results:** <!-- what did you want to see? -->
A smooth animation into the second page that has the camera preview.

**Actual results:** <!-- what did you see? -->
A stutter/pause when the scroll animation is initialized.

<details>
  <summary>Logs</summary>

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```
[√] Flutter (Channel stable, 2.2.3, on Microsoft Windows [Version 10.0.19043.1110], locale en-US)
    • Flutter version 2.2.3 at D:\dev\flutter_sdk\flutter_windows_2.2.1-stable\flutter
    • Framework revision f4abaa0735 (4 weeks ago), 2021-07-01 12:46:11 -0700
    • Engine revision 241c87ad80
    • Dart version 2.13.4

[√] Android toolchain - develop for Android devices (Android SDK version 30.0.3)
    • Android SDK at C:\Users\mike\AppData\Local\Android\sdk
    • Platform android-30, build-tools 30.0.3
    • Java binary at: C:\Program Files\Android\Android Studio\jre\bin\java
    • Java version OpenJDK Runtime Environment (build 11.0.8+10-b944.6842174)
    • All Android licenses accepted.

[√] Chrome - develop for the web
    • Chrome at C:\Program Files (x86)\Google\Chrome\Application\chrome.exe

[√] Android Studio
    • Android Studio at C:\Program Files\Android\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
    • android-studio-dir = C:\Program Files\Android\Android Studio
    • Java version OpenJDK Runtime Environment (build 11.0.8+10-b944.6842174)

[√] IntelliJ IDEA Community Edition (version 2019.1)
    • IntelliJ at C:\Program Files\JetBrains\IntelliJ IDEA Community Edition 2019.1.3
    • 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

[√] VS Code (version 1.32.3)
    • VS Code at C:\Users\mike\AppData\Local\Programs\Microsoft VS Code
    • Flutter extension can be installed from:
       https://marketplace.visualstudio.com/items?itemName=Dart-Code.flutter

[√] Connected device (3 available)
    • sdk gphone x86 (mobile) • emulator-5554 • android-x86    • Android 11 (API 30) (emulator)
    • Chrome (web)            • chrome        • web-javascript • Google Chrome 92.0.4515.107
    • Edge (web)              • edge          • web-javascript • Microsoft Edge 91.0.864.59

• No issues found!
```

</details>