setPolygonMode method
Filled or drawn as edges. Ask features.has(DeviceFeature.wireframe)
before naming PolygonMode.line: a backend that cannot draw it throws
UnsupportedCapabilityException rather than filling.
Implementation
@override
void setPolygonMode(PolygonMode mode) {
polygonMode = mode;
commands.add(RecordedPolygonMode(mode));
}