message: Improve points visualization in metrics_plotter.
  Cr-Commit-Position: refs/heads/main@{#34963}
diff: @@ -88,7 +88,8 @@ def main():
  plt.ylabel('%s (%s)' % (metric[GRAPH_NAME], metric[UNITS]))
  plt.xlabel('time (s)')
  plt.title(metric[GRAPH_NAME])
  - plt.plot(x_values, y_values)
  + plt.plot(x_values, y_values, marker='x', markersize=3,
  + markeredgecolor='red')
  plt.show()
  