Repository: flutter
Issue: WidgetTester.pageBack only work in an english application
Labels: a: tests,c: crash,framework,a: internationalization,f: routes,has reproducible steps,P2,found in release: 3.7,found in release: 3.8,team-framework,triaged-framework

WidgetTester has a method `pageBack` that tries to find a Back button.
```
    await tester.pumpWidget(MyWidget());
    await tester.tap(find.text('Button'));
    await tester.pageBack();
```

The implementation as shown here: https://api.flutter.dev/flutter/flutter_test/WidgetTester/pageBack.html, look for a tooltip with text "Back".
This doesn't work when the application is translated with MaterialLocalizations and the test runned in a language other than english.

The `pageBack` method should use an other technique to locate the button (ie. use a semantic label or search for a `BackButton` widget).

<details>
  <summary>Logs</summary>

<!--
      Run your application with `flutter run --verbose` and attach all the
      log output below between the lines with the backticks. If there is an
      exception, please see if the error message includes enough information
      to explain how to solve the issue.
-->

```
```

<!--
     Run `flutter analyze` and attach any output of that command below.
     If there are any analysis errors, try resolving them before filing this issue.
-->

```
```

<!-- Finally, paste the output of running `flutter doctor -v` here. -->

```
[✓] Flutter (Channel stable, v1.12.13+hotfix.8, on Mac OS X 10.15.2 19C57, locale en-BE)
    • Flutter version 1.12.13+hotfix.8 at /Users/xavier/projects/flutter_stable
    • Framework revision 0b8abb4724 (9 days ago), 2020-02-11 11:44:36 -0800
    • Engine revision e1e6ced81d
    • Dart version 2.7.0


[✓] Android toolchain - develop for Android devices (Android SDK version 29.0.2)
    • Android SDK at /Users/xavier/Library/Android/sdk
    • Android NDK location not configured (optional; useful for native profiling support)
    • Platform android-29, build-tools 29.0.2
    • Java binary at: /Applications/Android Studio.app/Contents/jre/jdk/Contents/Home/bin/java
    • Java version OpenJDK Runtime Environment (build 1.8.0_202-release-1483-b49-5587405)
    • All Android licenses accepted.

[✓] Xcode - develop for iOS and macOS (Xcode 11.3.1)
    • Xcode at /Applications/Xcode.app/Contents/Developer
    • Xcode 11.3.1, Build version 11C504
    • CocoaPods version 1.8.4

[✓] Android Studio (version 3.5)
    • Android Studio at /Applications/Android Studio.app/Contents
    • Flutter plugin version 43.0.1
    • Dart plugin version 191.8593
    • Java version OpenJDK Runtime Environment (build 1.8.0_202-release-1483-b49-5587405)

[✓] IntelliJ IDEA Ultimate Edition (version 2019.3.2)
    • IntelliJ at /Applications/IntelliJ IDEA.app
    • Flutter plugin version 43.0.3
    • Dart plugin version 193.6015.53

[✓] VS Code (version 1.41.1)
    • VS Code at /Applications/Visual Studio Code.app/Contents
    • Flutter extension version 3.7.1

[✓] Connected device (2 available)
    • Moto G 5 Plus   • ZY224FKBCL                • android-arm • Android 8.1.0 (API 27)
    • Xavier’s iPhone • 00008030-00012D9C0212802E • ios         • iOS 13.3.1

• No issues found!
```

</details>