void unbindFileFromDocument(@NotNull VirtualFile file, @NotNull Document document) {
    myDocumentCache.remove(file);
    file.putUserData(HARD_REF_TO_DOCUMENT_KEY, null);
    document.putUserData(FILE_KEY, null);
    fireFileBindingChanged(document, file, null);
  }
void unbindFileFromDocument(@NotNull VirtualFile file, @NotNull Document document)