private FoldingStructureComputationContext(IDocument document, ProjectionAnnotationModel model, boolean allowCollapsing, IScanner scanner) {
FoldingStructureComputationContext(IDocument document, ProjectionAnnotationModel model, boolean allowCollapsing) {
		private FoldingStructureComputationContext(IDocument document, ProjectionAnnotationModel model, boolean allowCollapsing, IScanner scanner) {			Assert.isNotNull(document);			Assert.isNotNull(model);			fDocument= document;			fModel= model;			fAllowCollapsing= allowCollapsing;			fScanner= scanner;		}