Bug 19014 Empty CU after reorg
F2 - enable single click and show in members in packages view - open TestCase.java in editor - give focus to packages view - change it on disk - copy a method in TestCase using DnD - activate the TestCase.java editor - answer question with no - activate revert from context menu observe: CU is empty
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/javaeditor/CompilationUnitDocumentProvider.java
cuInfo.fModel.removeAnnotationModelListener(fGlobalAnnotationModelListener);
		}
		
		super.disposeElementInfo(element, info);
	}
	
	/*
	 * @see AbstractDocumentProvider#doSaveDocument(IProgressMonitor, Object, IDocument, boolean)
	 */
	protected void doSaveDocument(IProgressMonitor monitor, Object element, IDocument document, boolean overwrite) throws CoreException {
				
		ElementInfo elementInfo= getElementInfo(element);		
		if (elementInfo instanceof CompilationUnitInfo) {
			CompilationUnitInfo info= (CompilationUnitInfo) elementInfo;
			
			
			info.fCopy.reconcile();
			
			ICompilationUnit original= (ICompilationUnit) info.fCopy.getOriginalElement();
			IResource resource= null;
			try {
				resource= original.getUnderlyingResource();
			} catch (JavaModelException x) {
				
			}
			
			if (resource == null) {
				
				super.doSaveDocument(monitor, element, document, overwrite);
				return;