Nested flows cause issues with Android's back button

[jeroen-meijer]

Describe the bug Nested flows cause unintended behavior on Android.

When two flows are nested inside each other, the back button on Android will close out the app.

To Reproduce N/A

Expected behavior The back button should close out of the inner flow and go back to the outer one.

flutter doctor -v output

``` [√] Flutter (Channel stable, 1.22.5, on Microsoft Windows [Version 10.0.18363.1256], locale en-US) • Flutter version 1.22.5 at C:\flutter • Framework revision 7891006299 (5 weeks ago), 2020-12-10 11:54:40 -0800 • Engine revision ae90085a84 • Dart version 2.10.4 [√] Android toolchain - develop for Android devices (Android SDK version 30.0.3) • Android SDK at C:\Users\sonic\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 1.8.0_242-release-1644-b01) • All Android licenses accepted. [!] Android Studio (version 4.1.0) • Android Studio at C:\Program Files\Android\Android Studio X Flutter plugin not installed; this adds Flutter specific functionality. X Dart plugin not installed; this adds Dart specific functionality. • Java version OpenJDK Runtime Environment (build 1.8.0_242-release-1644-b01) [√] VS Code (version 1.52.1) • VS Code at C:\Users\sonic\AppData\Local\Programs\Microsoft VS Code • Flutter extension version 3.18.1 [√] Connected device (1 available) • SM G950F (mobile) • ce031713eb22600102 • android-arm64 • Android 9 (API 28) ! Doctor found issues in 1 category. ```

Additional context I have discussed this issue in person with @felangel.

[felangel]

Possibly related to #12

[felangel]

@jeroen-meijer I wasn't able to reproduce with flow_builder: ^0.0.1-dev.11. Can you please re-test with the latest version and let me know if you're still able to reproduce the issue? Thanks! 🙏

[jeroen-meijer]

Correct, the issue is not present in the latest version. Good catch!

Closing. 👍🏻