[Telemetry] Move gpu_timeline metrics to telemetry.web_perf

tools/perf/metrics/test_page_test_results.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.
-
-from telemetry.page import page as page_module
-from telemetry.results import page_test_results
-from telemetry.value import scalar
-
-
-class TestPageTestResults(
-    page_test_results.PageTestResults):
-  def __init__(self, test):
-    super(TestPageTestResults, self).__init__()
-    self.test = test
-    page = page_module.Page("http://www.google.com", {})
-    self.WillRunPage(page)
-
-  def GetPageSpecificValueNamed(self, name):
-    values = [value for value in self.all_page_specific_values
-         if value.name == name]
-    assert len(values) == 1, 'Could not find value named %s' % name
-    return values[0]
-
-  def AssertHasPageSpecificScalarValue(self, name, units, expected_value):
-    value = self.GetPageSpecificValueNamed(name)
-    self.test.assertEquals(units, value.units)
-    self.test.assertTrue(isinstance(value, scalar.ScalarValue))
-    self.test.assertEquals(expected_value, value.value)
-
-  def __str__(self):
-    return '\n'.join([repr(x) for x in self.all_page_specific_values])