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
try {
				
				ICompilationUnit original= (ICompilationUnit) info.fCopy.getOriginalElement();
				IResource resource= original.getUnderlyingResource();
				if (resource instanceof IFile) {
					IFileEditorInput input= new FileEditorInput((IFile) resource);
					document= super.createDocument(input);
				} else
					document= new Document();
					
			} catch (CoreException x) {
				document= new Document();
				status= x.getStatus();
			}
			
			fireElementContentAboutToBeReplaced(element);
			
			removeUnchangedElementListeners(element, info);
			info.fDocument.set(document.get());
			info.fCanBeSaved= false;
			info.fStatus= status;
			addUnchangedElementListeners(element, info);
			
			fireElementContentReplaced(element);
			
		} else {
			super.resetDocument(element);
		}
	}