static getFontScale(): number {
    return Dimensions.get('window').fontScale || PixelRatio.get();
  }
Returns the scaling factor for font sizes. This is the ratio that is used to calculate the
absolute font size, so any elements that heavily depend on that should use this to do
calculations.

If a font scale is not set, this returns the device pixel ratio.

Currently this is only implemented on Android and reflects the user preference set in
Settings > Display > Font size, on iOS it will always return the default pixel ratio.
@platform android