[chromedriver] Add chrome.detach option for configuring Chrome not to quit

chrome/test/webdriver/commands/webdriver_command.cc

 // Copyright (c) 2011 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.
 
 #include "chrome/test/webdriver/commands/webdriver_command.h"
 
 #include <string>
 
 #include "base/logging.h"
 #include "base/memory/scoped_ptr.h"
@@ skipping 32 matching lines @@
 
   Error* error = session_->BeforeExecuteCommand();
   if (error) {
     response->SetError(error);
     return false;
   }
   response->SetField("sessionId", Value::CreateStringValue(session_id));
   return true;
 }
 
+void WebDriverCommand::Finish() {
+  scoped_ptr<Error> error(session_->AfterExecuteCommand());
+  if (error.get()) {
+    LOG(WARNING) << "Command did not finish successfully: "
+                 << error->GetErrorMessage();
+  }
+}
+
 }  // namespace webdriver