telemetry: add additional discrepancy test cases

tools/telemetry/telemetry/util/statistics_unittest.py

 # Copyright 2014 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 random
 import math
 
 from telemetry.util import statistics
 
@@ skipping 81 matching lines @@
     self.assertEquals(d, 1.0)
 
     samples = [0.5, 0.5, 0.5]
     d = statistics.Discrepancy(samples)
     self.assertEquals(d, 1.0)
 
     samples = [1.0/8.0, 3.0/8.0, 5.0/8.0, 7.0/8.0]
     d = statistics.Discrepancy(samples)
     self.assertEquals(d, 0.25)
 
+    samples = [1.0/8.0, 5.0/8.0, 5.0/8.0, 7.0/8.0]
+    d = statistics.Discrepancy(samples)
+    self.assertEquals(d, 0.5)
+
+    samples = [1.0/8.0, 3.0/8.0, 5.0/8.0, 5.0/8.0, 7.0/8.0]
+    d = statistics.Discrepancy(samples)
+    self.assertEquals(d, 0.4)
+
     samples = [0.0, 1.0/3.0, 2.0/3.0, 1.0]
     d = statistics.Discrepancy(samples)
     self.assertEquals(d, 0.5)
 
     samples = statistics.NormalizeSamples(samples)[0]
     d = statistics.Discrepancy(samples)
     self.assertEquals(d, 0.25)
 
   def testTimestampsDiscrepancy(self):
     time_stamps = []
@@ skipping 90 matching lines @@
     self.assertEquals(0, statistics.StandardDeviation([]))
 
   def testTrapezoidalRule(self):
     self.assertEquals(4, statistics.TrapezoidalRule([1, 2, 3], 1))
     self.assertEquals(2, statistics.TrapezoidalRule([1, 2, 3], .5))
     self.assertEquals(0, statistics.TrapezoidalRule([1, 2, 3], 0))
     self.assertEquals(-4, statistics.TrapezoidalRule([1, 2, 3], -1))
     self.assertEquals(3, statistics.TrapezoidalRule([-1, 2, 3], 1))
     self.assertEquals(0, statistics.TrapezoidalRule([1], 1))
     self.assertEquals(0, statistics.TrapezoidalRule([0], 1))