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
IWorkbenchPage page= getSite().getPage();
				IViewPart view= view= page.findView("org.eclipse.ui.views.TaskList"); 
				if (view instanceof TaskList) {
					StructuredSelection ss= new StructuredSelection(marker);
					((TaskList) view).setSelection(ss, true);
				}
			}
			
			selectAndReveal(annotationPosition.getOffset(), annotationPosition.getLength());
			if (nextAnnotation.isProblem())
				setStatusLineErrorMessage(nextAnnotation.getMessage());
		}
	}
	
	/**
	 * Jumps to the matching bracket.
	 */
	public void gotoMatchingBracket() {
		
		ISourceViewer sourceViewer= getSourceViewer();
		IDocument document= sourceViewer.getDocument();
		if (document == null)
			return;
		
		IRegion selection= getSignedSelection(sourceViewer);
		int selectionLength= Math.abs(selection.getLength());
		if (selectionLength > 1) {
			setStatusLineErrorMessage(JavaEditorMessages.getString("GotoMatchingBracket.error.invalidSelection"));			
			sourceViewer.getTextWidget().getDisplay().beep();
			return;