@Nullable
  public static String getPackageName(final GrFileStub stub) {
    for (StubElement child : stub.getChildrenStubs()) {
      if (child instanceof GrPackageDefinitionStub) {
        return ((GrPackageDefinitionStub)child).getPackageName();
      }
    }
    return null;
  }
@Nullable
  public static String getPackageName(final GrFileStub stub)