Create a UKM descriptions XML file

tools/metrics/ukm/pretty_print_test.py

Index: tools/metrics/ukm/pretty_print_test.py
diff --git a/tools/metrics/ukm/pretty_print_test.py b/tools/metrics/ukm/pretty_print_test.py
new file mode 100755
index 0000000000000000000000000000000000000000..8f23cd7f02f04c9e99f6ce3a18fd8020d7de5ad9
--- /dev/null
+++ b/tools/metrics/ukm/pretty_print_test.py
@@ -0,0 +1,42 @@
+#!/usr/bin/env python
+# Copyright 2017 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+import unittest
+
+import model
+
+
+PRETTY_XML = """
+<!-- Comment1 -->
+
+<ukm-configuration>
+
+<event name="Event1">
+  <owner>owner@chromium.org</owner>
+  <summary>
+    Event1 summary.
+  </summary>
+  <metric name="Metric1">
+    <owner>owner2@chromium.org</owner>
+    <summary>
+      Metric1 summary.
+    </summary>
+  </metric>
+  <metric name="Metric2"/>
+</event>
+
+</ukm-configuration>
+""".strip()
+
+
+class UkmXmlTest(unittest.TestCase):
+
+  def testIsPretty(self):
+    result = model.UpdateXML(PRETTY_XML)
+    self.assertMultiLineEqual(PRETTY_XML, result.strip())
+
+
+if __name__ == '__main__':
+  unittest.main()