[telemetry] Sort imports in Telemetry and its dependents.

tools/perf/benchmarks/start_with_url.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 import benchmark
+
 from measurements import startup
 import page_sets
-from telemetry import benchmark
 
 
 class _StartWithUrl(benchmark.Benchmark):
   page_set = page_sets.StartupPagesPageSet
   test = startup.StartWithUrl
 
   @classmethod
   def Name(cls):
     return 'start_with_url.startup_pages'
 
@@ skipping 17 matching lines @@
 @benchmark.Enabled('has tabs')
 @benchmark.Disabled('chromeos', 'linux', 'mac', 'win')
 class StartWithUrlWarm(_StartWithUrl):
   """Measure time to start Chrome warm with startup URLs"""
   tag = 'warm'
   options = {'pageset_repeat': 10}
   @classmethod
   def Name(cls):
     return 'start_with_url.warm.startup_pages'