Revert "remove outdated unused method, https://github.com/phetsims/phet-core/issues/98"
Revert "remove outdated unused method, https://github.com/phetsims/phet-core/issues/98"

This reverts commit db98018163c6b2ba1ba009316ec054a0a7260046.

phetsims/phet-core,phetsims/phet-core,phetsims/phet-core