[telemetry] Prototype for specifying page sets using Python imports and Telemetry discovery.

tools/telemetry/telemetry/core/environment.py

-# Copyright (c) 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.
-
-
-class Environment(object):
-  def __init__(self, base_paths, test_aliases=None):
-    self._base_paths = base_paths
-    if test_aliases:
-      self._test_aliases = test_aliases
-    else:
-      self._test_aliases = {}
-
-  @property
-  def base_paths(self):
-    return self._base_paths
-
-  @property
-  def test_aliases(self):
-    return self._test_aliases