title: "UnreachableBrowserException" and "UnixUtils may not be used on Windows exception" after driver.quit while using MarionetteDriver
body: <p>Environment- Firefox 48.0.2 and Selenium 3.0.0-beta2 versions ,i am getting below error -</p>
  
  <blockquote>
    <p>1472824777259 Marionette  INFO    Listening on port 61096 [Child 5848]
    WARNING: pipe error: 109: file
    c:/builds/moz2_slave/m-rel-w32-00000000000000000000/build/src/ipc/chromium/src/chrome/common/ipc_channel_win.cc,
    line 343</p>
    
    <p>[Child 4048] ###!!! ABORT: Aborting on channel error.: file
    c:/builds/moz2_slave/m-rel-w32-00000000000000000000/build/src/ipc/glue/MessageChannel.cpp,
    line 2046 Exception in thread "main"
    org.openqa.selenium.remote.UnreachableBrowserException: Error
    communicating with the remote browser. It may have died. Build info:
    version: '3.0.0-beta2', revision: '2aa21c1', time: '2016-08-02
    15:03:28 -0700' System info: host: 'VM7-JDB-068', ip: '10.60.88.67',
    os.name: 'Windows 7', os.arch: 'amd64', os.version: '6.1',
    java.version: '1.8.0_51' Driver info: driver.version: RemoteWebDriver
    Capabilities [{rotatable=false, raisesAccessibilityExceptions=false,
    marionette=true, appBuildId=20160823121617, version=, platform=XP,
    proxy={}, command_id=1, specificationLevel=0, acceptSslCerts=false,
    browserVersion=48.0.2, platformVersion=6.1,
    XULappId={ec8030f7-c20a-464f-9b0e-13a3a9e97384}, browserName=Firefox,
    takesScreenshot=true, takesElementScreenshot=true,
    platformName=Windows_NT, device=desktop}] Session ID:
    499ab4bb-406d-4252-8b5d-808b22831595  at
    org.openqa.selenium.remote.RemoteWebDriver.execute(RemoteWebDriver.java:670)
      at
    org.openqa.selenium.remote.RemoteWebDriver.execute(RemoteWebDriver.java:706)
      at
    org.openqa.selenium.remote.RemoteWebDriver.quit(RemoteWebDriver.java:531)
      at firefox_java.sample.main(sample.java:19) Caused by:
    java.lang.IllegalStateException: UnixUtils may not be used on Windows
      at
    org.openqa.selenium.os.ProcessUtils.getProcessId(ProcessUtils.java:188)
      at
    org.openqa.selenium.os.UnixProcess$SeleniumWatchDog.getPID(UnixProcess.java:222)
      at
    org.openqa.selenium.os.UnixProcess$SeleniumWatchDog.access$300(UnixProcess.java:201)
      at org.openqa.selenium.os.UnixProcess.destroy(UnixProcess.java:132)
      at org.openqa.selenium.os.CommandLine.destroy(CommandLine.java:155)
      at
    org.openqa.selenium.remote.service.DriverService.stop(DriverService.java:196)
      at
    org.openqa.selenium.remote.service.DriverCommandExecutor.execute(DriverCommandExecutor.java:94)
      at
    org.openqa.selenium.remote.RemoteWebDriver.execute(RemoteWebDriver.java:649)
      ... 3 more  on    driver.quit();</p>
  </blockquote>
  
  <p>Here is my Java code:</p>
  
  <pre><code> String marionetteDriverLocation = "\\Lib\\geckodriver.exe";  
   System.setProperty("webdriver.gecko.driver", marionetteDriverLocation);  
   WebDriver driver = new FirefoxDriver();  
   driver.get("https://www.google.co.in");
  
   driver.quit();  
  </code></pre>
  
  <p>Could you please help .
      Thanks</p>