Add missing import in chrome_startup_controller.py.

tools/profile_chrome/chrome_startup_controller.py

 # Copyright 2015 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
 import time
 
 from pylib import flag_changer
+from pylib.device import intent
 from pylib.perf import cache_control
 
 from profile_chrome import controllers
 
 class ChromeStartupTracingController(controllers.BaseController):
   def __init__(self, device, package_info, cold, url):
     self._device = device
     self._package_info = package_info
     self._cold = cold
     self._logcat_monitor = self._device.GetLogcatMonitor()
@@ skipping 12 matching lines @@
     changer.AddFlags(['--trace-startup'])
     self._device.ForceStop(self._package_info.package)
     if self._cold:
       self._device.EnableRoot()
       cache_control.CacheControl(self._device).DropRamCaches()
     self._device.StartActivity(
         intent.Intent(
             package=self._package_info.package,
             activity=self._package_info.activity,
             data=self._url,
-            extras={'create_new_tab' : True}))
+            extras={'create_new_tab' : True}), blocking=True)
 
   def _TearDownTracing(self):
     changer = flag_changer.FlagChanger(
         self._device, self._package_info.cmdline_file)
     changer.RemoveFlags(['--trace-startup'])
 
   def StartTracing(self, interval):
     self._SetupTracing()
     self._logcat_monitor.Start()
 
   def StopTracing(self):
     try:
       self._trace_file = self._logcat_monitor.WaitFor(
           self._trace_finish_re).group(1)
     finally:
       self._TearDownTracing()
 
   def PullTrace(self):
     # Wait a bit for the browser to finish writing the trace file.
     time.sleep(3)
     trace_file = self._trace_file.replace('/storage/emulated/0/', '/sdcard/')
     host_file = os.path.join(os.path.curdir, os.path.basename(trace_file))
     self._device.PullFile(trace_file, host_file)
     return host_file