Re: [sensors] Investigate possibility of synchronizing coordinate systems

I think from practical perspective `partial dictionary SensorOptions { CoordinateSystem coordinateSystem; }` and `dictionary TriaxialSensorOptions : SensorOptions {  CoordinateSystem coordinateSystem  }` are equivalent. However in the later case we can explicitly mention where `TriaxialSensorOptions` can be used, i.e.
```
[Constructor(optional TriaxialSensorOptions options),
 SecureContext, Exposed=Window]
interface AbsoluteOrientationSensor : OrientationSensor {
};
```

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