code: @VisibleForTesting
    @GwtIncompatible("Unnecessary")
    void printManifestTo(Iterable<CompilerInput> inputs, Appendable out) throws IOException {
      for (CompilerInput input : inputs) {
        String rootRelativePath = rootRelativePathsMap.get(input.getName());
        String displayName = rootRelativePath != null
            ? rootRelativePath
            : input.getName();
        out.append(displayName);
        out.append("\n");
      }
    }
docs: Prints a list of input names (using root-relative paths), delimited by newlines, to the
  manifest file.