Bug 43488 [typing] BadPositionCategoryException in LinkedPositionManager
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/javaeditor/JavaEditor.java
if (widget != null && !widget.isDisposed()) {
							widget.getDisplay().asyncExec(new Runnable() {
								public void run() {
									deactivate();
								}
							});
						}
					}
					
				} else {
					fActiveRegion= null;
					fRememberedPosition= null;
					deactivate();
				}
			}
		}
		/*
		 * @see org.eclipse.jface.text.ITextInputListener#inputDocumentAboutToBeChanged(org.eclipse.jface.text.IDocument, org.eclipse.jface.text.IDocument)
		 */
		public void inputDocumentAboutToBeChanged(IDocument oldInput, IDocument newInput) {
			if (oldInput == null)
				return;
			deactivate();
			oldInput.removeDocumentListener(this);
		}
		/*
		 * @see org.eclipse.jface.text.ITextInputListener#inputDocumentChanged(org.eclipse.jface.text.IDocument, org.eclipse.jface.text.IDocument)
		 */
		public void inputDocumentChanged(IDocument oldInput, IDocument newInput) {
			if (newInput == null)