public void addModifiedWidget(ConstraintWidget widget){
  if (mModifiedWidgets.contains(widget)) {
    return;
  }
  mModifiedWidgets.add(widget);
}

public void addModifiedWidget ( ConstraintWidget widget ) { if ( mModifiedWidgets . contains ( widget ) ) { return ; } mModifiedWidgets . add ( widget ) ; }
add a widget to the list of modified widgets
