@Nullable
  private static FileAnnotationLoader createAnnotationsLoader(@NotNull Project project, @NotNull DiffContent content) {
    if (content instanceof FileContent) {
      VirtualFile file = ((FileContent)content).getFile();
      AbstractVcs vcs = VcsUtil.getVcsFor(project, file);
      FileAnnotationLoader loader = doCreateAnnotationsLoader(project, vcs, file);
      if (loader != null) return loader;
    }

    Pair<FilePath, VcsRevisionNumber> info = content.getUserData(DiffVcsDataKeys.REVISION_INFO);
    if (info != null) {
      FilePath filePath = info.first;
      AbstractVcs vcs = VcsUtil.getVcsFor(project, filePath);
      FileAnnotationLoader loader = doCreateAnnotationsLoader(vcs, filePath, info.second);
      if (loader != null) return loader;
    }
    return null;
  }
@Nullable
  private static FileAnnotationLoader createAnnotationsLoader(@NotNull Project project, @NotNull DiffContent content)