Address duplicated code

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Re this CRC item:

• Are any significant chunks of code duplicated? In addition to manual identification, tools include: WebStorm Code > Analyze Code > Locate Duplicates and https://github.com/danielstjules/jsinspect.

I used WebStorm's Locate Duplicates feature, and addressed duplicates that I thought were significant. This issue documents duplicates that I did not address that might be controversial.

(1) ElectromagnetScreenView, TransformerScreenView, and GeneratorScreenView have the same pdomOrder for the control area, and that results in the bit of duplicated code shown below. BarMagnetScreenView and PickupCoilScreenView have a similar relationship. At the ScreenView level, I feel that it's more readable and more maintainable to explicitly show the complete pdomOrder for both play area and control area. So I'm not only fine with this bit of duplication, I prefer it.

    this.pdomControlAreaNode.pdomOrder = [
      panels.toolsPanel,
      timeControlNode,
      this.resetAllButton
    ];

(2) FELSonifier, FieldMeterDragSonifier, CompassSonifier contain some duplicated code. This is experimental sonification code (documented as such), not included in the production version, likely to evolve in a future release. So the duplicatation here does not concern me.

(3) Layout of pickupCoilDebuggerPanel is duplicated in the 3 ScreenView subclasses that involve a pickup coil. This is a debugging tool, not part of the production UI, and I don't feel the need to factor this out.

    pickupCoilDebuggerPanel.centerX = this.layoutBounds.centerX;
    pickupCoilDebuggerPanel.top = this.layoutBounds.top + FELConstants.SCREEN_VIEW_Y_MARGIN;

(4) BarMagnetScreenView and PickupCoilScreenView both use the same type of compass and do not have time controls. The code below is mostly duplicated, except that the compass is not visible in the Pickup Coil screen. At the ScreenView level, I don't feel the need to complicate things by factoring this out.

    super( barMagnet, {
      createCompass: ( magnet, isPlayingProperty, tandem ) => new KinematicCompass( magnet, isPlayingProperty, {
        position: new Vector2( 625, 400 ),
-       visible: false,
        tandem: tandem
      } ),
      isPlayingPropertyOptions: {
        tandem: Tandem.OPT_OUT // because this screen has no time controls
      },
      tandem: tandem
    } );

(5) PickupCoilScreenView and TransformerScreenView have the "Lock to Axis" feature, and therefore the isLockedToAxisProperty shown below. How isLockedToAxisProperty is subsequently used by these screens is very different. So I don't feel a need to factor this out.

    const isLockedToAxisProperty = new BooleanProperty( false, {
      tandem: tandem.createTandem( 'isLockedToAxisProperty' ),
      phetioDocumentation: 'When true, dragging the magnet or pickup coil is locked to the pickup coil\'s horizontal axis.'
    } );

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I address duplicated code that I thought was significant in the above commits. Closing.