[Telemetry] Add capability for values to reference external files.

tools/telemetry/telemetry/results/page_test_results_unittest.py

Index: tools/telemetry/telemetry/results/page_test_results_unittest.py
diff --git a/tools/telemetry/telemetry/results/page_test_results_unittest.py b/tools/telemetry/telemetry/results/page_test_results_unittest.py
index 4de065b91c84fb10dfad2cd4a7958e03be0b2894..2ac43dd201444d5e0442d346e5d207db05374bde 100644
--- a/tools/telemetry/telemetry/results/page_test_results_unittest.py
+++ b/tools/telemetry/telemetry/results/page_test_results_unittest.py
@@ -59,6 +59,19 @@ class PageTestResultsTest(base_test_results_unittest.BaseTestResultsUnittest):
     self.assertTrue(results.all_page_runs[0].skipped)
     self.assertTrue(results.all_page_runs[1].ok)
 
+  def testPathsAreNormalized(self):
+    results = page_test_results.PageTestResults()
+    file0 = './foo.txt'
+    file1 = 'foo.txt'
+    expected_path = os.path.normcase(os.path.realpath(file1))
+    v0 = scalar.ScalarValue(None, 'foo', 'seconds', 3, paths=[file0])
+    v1 = scalar.ScalarValue(None, 'foo', 'seconds', 3, paths=[file1])
+    results.AddSummaryValue(v0)
+    results.AddSummaryValue(v1)
+
+    self.assertEqual(len(results.all_paths), 1)
+    self.assertEqual(list(results.all_paths)[0], expected_path)
+
   def test_basic(self):
     results = page_test_results.PageTestResults()
     results.WillRunPage(self.pages[0])