chromium/tools/metrics/histograms/test_data/components/histograms.xml

<histogram-configuration>

<histograms>

<histogram name="Test.Histogram" units="seconds" expires_after="M104">
  <owner>[email protected]</owner>
  <owner>[email protected]</owner>
  <summary>Summary 2</summary>
</histogram>

<histogram name="Test.Histogram.WithComponent" enum="TestEnum"
    expires_after="M104">
  <owner>[email protected]</owner>
  <owner>[email protected]</owner>
  <component>First&gt;Component</component>
  <summary>A enum histogram.</summary>
</histogram>

</histograms>

</histogram-configuration>