Adds two convenience functions for later use.

infra/libs/time_functions/test/timestamp_test.py

Index: infra/libs/time_functions/test/timestamp_test.py
diff --git a/infra/libs/time_functions/test/timestamp_test.py b/infra/libs/time_functions/test/timestamp_test.py
new file mode 100644
index 0000000000000000000000000000000000000000..aa5256f35e858a8bb7c5caf2d319a1f8639961a2
--- /dev/null
+++ b/infra/libs/time_functions/test/timestamp_test.py
@@ -0,0 +1,24 @@
+# Copyright 2015 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 datetime
+from pytz import timezone
+import unittest
+
+from infra.libs.time_functions import timestamp
+
+
+class TestTimestamps(unittest.TestCase):
+  def testTimestamp(self):
+    sec_diff = 1000
+    my_date = datetime.datetime.utcfromtimestamp(sec_diff)
+    self.assertEqual(timestamp.utctimestamp(my_date), float(sec_diff))
+
+  def testTimeZoneTimestamp(self):
+    sec_diff = 1000
+    my_date = datetime.datetime.utcfromtimestamp(sec_diff)
+    my_date = my_date.replace(tzinfo=timezone('Etc/GMT-8'))
+
+    pst_diff = sec_diff - (8 * 3600.0)
+    self.assertEqual(timestamp.utctimestamp(my_date), float(pst_diff))