[telemetry] Support absolute paths by changing file:/// to file://. More robust file path handling.

tools/perf/benchmarks/sunspider.py

 # Copyright (c) 2013 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 collections
 import json
 import os
 
 from telemetry import test
 from telemetry.core import util
 from telemetry.page import page_measurement
@@ skipping 28 matching lines @@
 
 class Sunspider(test.Test):
   """Apple's SunSpider JavaScript benchmark."""
   test = SunspiderMeasurement
 
   def CreatePageSet(self, options):
     sunspider_dir = os.path.join(util.GetChromiumSrcDir(),
                                  'chrome', 'test', 'data', 'sunspider')
     return page_set.PageSet.FromDict(
         {
-          'serving_dirs': [''],
-          'pages': [{ 'url': 'file:///sunspider-1.0/driver.html' }],
+          'serving_dirs': ['.'],
+          'pages': [{ 'url': 'file://sunspider-1.0/driver.html' }],
         },
         sunspider_dir)