private @NotNull Map<VirtualFile, VcsLogProvider> getProvidersForRoots(@NotNull Set<? extends VirtualFile> roots) {
    return ContainerUtil.map2Map(roots, root -> Pair.create(root, myProviders.get(root)));
  }
private @NotNull Map<VirtualFile, VcsLogProvider> getProvidersForRoots(@NotNull Set<? extends VirtualFile> roots)