Change mojo url to always use mojo:foo instead of mojo://foo

sky/tools/test_perf

 #!/usr/bin/env python
 # 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 os
 import re
 from skypy.paths import Paths
 import subprocess
 import requests
@@ skipping 53 matching lines @@
         self.paths = Paths(os.path.join('out', 'Debug'))
 
     def _start_server(self):
         return subprocess.Popen([
             os.path.join(self.paths.sky_tools_directory, 'sky_server'),
             self.paths.src_root,
             str(HTTP_PORT),
         ])
 
     def _sky_tester_command(self, url):
-        content_handlers = ['%s,%s' % (mime_type, 'mojo://sky_viewer/')
+        content_handlers = ['%s,%s' % (mime_type, 'mojo:sky_viewer')
             for mime_type in SUPPORTED_MIME_TYPES]
         return [
             self.paths.mojo_shell_path,
-            '--args-for=mojo://native_viewport_service/ --use-headless-config --use-osmesa',
-            '--args-for=mojo://window_manager/ %s' % url,
+            '--args-for=mojo:native_viewport_service --use-headless-config --use-osmesa',
+            '--args-for=mojo:window_manager %s' % url,
             '--content-handlers=%s' % ','.join(content_handlers),
-            '--url-mappings=mojo:window_manager=mojo://sky_tester/',
+            '--url-mappings=mojo:window_manager=mojo:sky_tester',
             'mojo:window_manager',
         ]
 
 
     def main(self):
         test = 'http://localhost:9999/sky/benchmarks/layout/simple-blocks.sky'
 
         self._start_server()
         output = subprocess.check_output(self._sky_tester_command(test))
         values = values_from_output(output)
         json = create_json_blob(values)
         send_json_to_dashboard(json)
 
     def shutdown(self):
         if self._sky_server:
             self._sky_server.terminate()
 
 
 if __name__ == '__main__':
     harness = PerfHarness()
     try:
         harness.main()
     except (KeyboardInterrupt, SystemExit):
         pass
     finally:
         harness.shutdown()