ConstraintType     57 Source/core/page/scrolling/ScrollingConstraints.h     virtual ConstraintType constraintType() const = 0;
ConstraintType    107 Source/core/page/scrolling/ScrollingConstraints.h     virtual ConstraintType constraintType() const OVERRIDE { return FixedPositionConstaint; }
ConstraintType    175 Source/core/page/scrolling/ScrollingConstraints.h     virtual ConstraintType constraintType() const OVERRIDE { return StickyPositionConstraint; }