code: public final void setDialogScrollableArea(@Nullable final Area top,
                                                @Nullable final Area bottom) {
          this.dialogScrollableArea = ScrollableArea.create(top, bottom);
      }
docs: Sets the scrollable area of the preference's dialog.
  
  @param top
  The top scrollable area, which should be set, as a value of the enum Area or null, if
  no scrollable area should be set
  @param bottom
  The bottom scrollable area, which should be set, as a value of the enum Area or null,
  if no scrollable area should be set. The index of the bottom area must be at leas the
  index of the top area. If the top area is null, the bottom area must be null as well