[chromedriver] Implement command: switchToWindow.

chrome/test/chromedriver/session_commands.h

 // Copyright (c) 2013 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.
 
 #ifndef CHROME_TEST_CHROMEDRIVER_SESSION_COMMANDS_H_
 #define CHROME_TEST_CHROMEDRIVER_SESSION_COMMANDS_H_
 
 #include <string>
 
 #include "base/callback_forward.h"
@@ skipping 36 matching lines @@
     Session* session,
     const base::DictionaryValue& params,
     scoped_ptr<base::Value>* value);
 
 // Retrieve the list of all window handles available to the session.
 Status ExecuteGetWindowHandles(
     Session* session,
     const base::DictionaryValue& params,
     scoped_ptr<base::Value>* value);
 
+// Change focus to another window. The window to change focus to may be
+// specified by its server assigned window handle, or by the value of its name
+// attribute.
+Status ExecuteSwitchToWindow(
+    Session* session,
+    const base::DictionaryValue& params,
+    scoped_ptr<base::Value>* value);
+
 // Configure the amount of time that a particular type of operation can execute
 // for before they are aborted and a timeout error is returned to the client.
 Status ExecuteSetTimeout(
     Session* session,
     const base::DictionaryValue& params,
     scoped_ptr<base::Value>* value);
 
 #endif  // CHROME_TEST_CHROMEDRIVER_SESSION_COMMANDS_H_