updateChildLayoutOffset abstract method Null safety
Called during layoutChildSequence to store the layout offset for the given child.
Different subclasses using different representations for their children's layout offset (e.g., logical or physical coordinates). This function lets subclasses transform the child's layout offset before storing it in the child's parent data.
@protected void updateChildLayoutOffset(RenderSliver child, double layoutOffset, GrowthDirection growthDirection);