@Override
  public void applyFix(@NotNull final Project project, @NotNull ProblemDescriptor descriptor) {
    PsiElement element = descriptor.getPsiElement();
    if (element == null) {  // stale PSI
      return;
    }
    final PsiFile file = element.getContainingFile();
    optimizeImports(project, file);
  }
@Override
  public void applyFix(@NotNull final Project project, @NotNull ProblemDescriptor descriptor)