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/CompilationUnitDocumentProvider.java
try {
				String encoding= getEncoding(element);
				if (encoding == null)
					encoding= ResourcesPlugin.getEncoding();
				InputStream stream= new ByteArrayInputStream(document.get().getBytes(encoding));
				IFile file= input.getFile();
				file.setContents(stream, overwrite, true, monitor);
			} catch (IOException x)  {
				IStatus s= new Status(IStatus.ERROR, JavaUI.ID_PLUGIN, IStatus.OK, x.getMessage(), x);
				throw new CoreException(s);
			}
		}
	}
	
	/*
	 * @see org.eclipse.jdt.internal.ui.javaeditor.ICompilationUnitDocumentProvider#shutdown()
	 */
	public void shutdown() {
		
		JavaPlugin.getDefault().getPreferenceStore().removePropertyChangeListener(fPropertyListener);
		
		Iterator e= getConnectedElements();
		while (e.hasNext())
			disconnect(e.next());
	}
	
	/*
	 * @see org.eclipse.jdt.internal.ui.javaeditor.ICompilationUnitDocumentProvider#addGlobalAnnotationModelListener(org.eclipse.jface.text.source.IAnnotationModelListener)
	 */
	public void addGlobalAnnotationModelListener(IAnnotationModelListener listener) {