Bug 40785 [plan item] Overview ruler improvements
- navigation from ruler to editor - hovering over header area shows number of errors/warning (header annotations in general)
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/javaeditor/JavaEditor.java
containingAnnotation= a;
					containingAnnotationPosition= p;
					if (length == p.length)
						currentAnnotation= true;
			}
		}
		}
		if (containingAnnotationPosition != null && (!currentAnnotation || nextAnnotation == null)) {
			annotationPosition.setOffset(containingAnnotationPosition.getOffset());
			annotationPosition.setLength(containingAnnotationPosition.getLength());
			return containingAnnotation;
		}
		if (nextAnnotationPosition != null) {
			annotationPosition.setOffset(nextAnnotationPosition.getOffset());
			annotationPosition.setLength(nextAnnotationPosition.getLength());
		}
		
		return nextAnnotation;
	}
	
	/**
	 * Computes and returns the source reference that includes the caret and
	 * serves as provider for the outline page selection and the editor range
	 * indication.
	 * 
	 * @return the computed source reference
	 * @since 3.0
	 */
	protected ISourceReference computeHighlightRangeSourceReference() {
		ISourceViewer sourceViewer= getSourceViewer();