title: WebDriverException thrown in Python for Selenium driver for Chrome
body: <p>I ran the following commands in Python to instantiate a Selenium webdriver for Chrome, but got an exception. Previously (a few days ago) there was no error:</p>
  
  <pre><code>from selenium import webdriver
  driver = webdriver.chrome.webdriver.WebDriver()
  Traceback (most recent call last):
    File "&lt;stdin&gt;", line 1, in &lt;module&gt;
    File "C:\Python27\lib\site-packages\selenium\webdriver\chrome\webdriver.py", line 65, in __init__
      keep_alive=True)
    File "C:\Python27\lib\site-packages\selenium\webdriver\remote\webdriver.py", line 74, in __init__
      self.start_session(desired_capabilities, browser_profile)
    File "C:\Python27\lib\site-packages\selenium\webdriver\remote\webdriver.py", line 123, in start_session
      'desiredCapabilities': desired_capabilities,
    File "C:\Python27\lib\site-packages\selenium\webdriver\remote\webdriver.py", line 175, in execute
      self.error_handler.check_response(response)
    File "C:\Python27\lib\site-packages\selenium\webdriver\remote\errorhandler.py", line 166, in check_response
      raise exception_class(message, screen, stacktrace)
  selenium.common.exceptions.WebDriverException: Message: session not created exception
  from unknown error: Runtime.executionContextCreated has invalid 'context': {"aux
  Data":{"frameId":"9716.1","isDefault":true},"id":1,"name":"","origin":"://"}
    (Session info: chrome=54.0.2840.71)
    (Driver info: chromedriver=2.22.397933 (1cab651507b88dec79b2b2a22d1943c01833cc
  1b),platform=Windows NT 6.1.7601 SP1 x86_64)
  </code></pre>
  
  <p>There are also errors of the form:</p>
  
  <pre><code>  File "C:\Python27\lib\site-packages\selenium\webdriver\chrome\webdriver.py", line 67, in __init__
      desired_capabilities=desired_capabilities)
    File "C:\Python27\lib\site-packages\selenium\webdriver\remote\webdriver.py", line 87, in __init__
      self.start_session(desired_capabilities, browser_profile)
    File "C:\Python27\lib\site-packages\selenium\webdriver\remote\webdriver.py", line 141, in start_session
      'desiredCapabilities': desired_capabilities,
    File "C:\Python27\lib\site-packages\selenium\webdriver\remote\webdriver.py", line 199, in execute
      response = self.command_executor.execute(driver_command, params)
    File "C:\Python27\lib\site-packages\selenium\webdriver\remote\remote_connection.py", line 395, in execute
      return self._request(command_info[0], url, body=data)
    File "C:\Python27\lib\site-packages\selenium\webdriver\remote\remote_connection.py", line 426, in _request
      resp = self._conn.getresponse()
    File "C:\Python27\lib\httplib.py", line 1132, in getresponse
      response.begin()
    File "C:\Python27\lib\httplib.py", line 453, in begin
      version, status, reason = self._read_status()
    File "C:\Python27\lib\httplib.py", line 409, in _read_status
      line = self.fp.readline(_MAXLINE + 1)
    File "C:\Python27\lib\socket.py", line 480, in readline
      data = self._sock.recv(self._rbufsize)
  socket.error: [Errno 10054] An existing connection was forcibly closed by the remote host
  </code></pre>