Steps to reproduce

1. Create a fresh Flutter app and add a dependency that touches flutter_gpu on the first frame (e.g. flutter_scene). Any access to gpu.gpuContext triggers the runtime check.
2. Connect an Android device with Vulkan-Impeller support (reproduced on Pixel 10 Pro, Android 16 / API 36).
3. Run with the documented opt-in flag, without adding any manifest metadata:

   flutter run -d <android-device> --enable-flutter-gpu --enable-impeller

Expected results

The app launches with Flutter GPU enabled, matching the runtime error message which lists --enable-flutter-gpu as a valid way to opt in (engine/src/flutter/lib/gpu/context.cc:53–58):

Flutter GPU must be enabled via the Flutter GPU manifest setting. This can be done either via command line argument --enable-flutter-gpu or by adding the FLTEnableFlutterGPU key set to true in the Info.plist on iOS/macOS, or the io.flutter.embedding.android.EnableFlutterGPU metadata key to true in the AndroidManifest.xml on Android.

…and matching the documented behavior on iOS/macOS where the CLI flag alone is sufficient.

Actual results

The app throws:

Exception: Flutter GPU must be enabled via the Flutter GPU manifest setting. This can be done
either via command line argument --enable-flutter-gpu or by adding the FLTEnableFlutterGPU
key set to true in the Info.plist on iOS/macOS, or the
io.flutter.embedding.android.EnableFlutterGPU metadata key to true in the AndroidManifest.xml
on Android.

repeatedly on every frame, because dart_state->IsFlutterGPUEnabled() returns false (engine/src/flutter/lib/gpu/context.cc:51).

Adding the manifest opt-in to android/app/src/main/AndroidManifest.xml works around it:

<meta-data
    android:name="io.flutter.embedding.android.EnableFlutterGPU"
    android:value="true" />

Test matrix

Same minimal app, no FLTEnableFlutterGPU in Info.plist, no EnableFlutterGPU in AndroidManifest.xml unless noted.

So the CLI flag enables the API on iOS and macOS but not Android.

Where it diverges

• iOS: FlutterDartProject.mm:226–228 reads the Info.plist key. The --enable-flutter-gpu switch also reaches settings.enable_flutter_gpu via the cross-platform path in shell/common/switches.cc:553, so either path works.
• macOS: FlutterDartProject.mm:97 reads the Info.plist key, plus the cross-platform switch path. Either works.
• Android: FlutterEngineFlags.java:232 defines new Flag(\"--enable-flutter-gpu\", \"EnableFlutterGPU\", true); and FlutterLoader reads the EnableFlutterGPU manifest meta-data and converts it into the --enable-flutter-gpu engine switch. The flutter run --enable-flutter-gpu argument from the tool side does not appear to flow through to the engine's switch list, so settings.enable_flutter_gpu stays false.

Suggested fix

Make flutter run --enable-flutter-gpu propagate to the Android engine launch (add it to the engine arg list the tool passes to FlutterLoader / the activity) so the documented behavior is consistent with iOS/macOS.

Flutter version

Flutter 3.44.0-1.0.pre-380
Tools • Dart 3.13.0

Reproducible on the master channel; the code paths cited above are current.