[Chromedriver] Chromedriver should handle unexpected alert automatically.

chrome/test/chromedriver/session.h

 // Copyright (c) 2012 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_H_
 #define CHROME_TEST_CHROMEDRIVER_SESSION_H_
 
 #include <list>
 #include <memory>
 #include <string>
 
 #include "base/files/scoped_temp_dir.h"
 #include "base/memory/scoped_vector.h"
 #include "base/time/time.h"
 #include "chrome/test/chromedriver/basic_types.h"
 #include "chrome/test/chromedriver/chrome/device_metrics.h"
 #include "chrome/test/chromedriver/chrome/geoposition.h"
 #include "chrome/test/chromedriver/chrome/network_conditions.h"
 #include "chrome/test/chromedriver/command_listener.h"
 
+static const char kAccept[] = "accept";
+static const char kDismiss[] = "dismiss";
+static const char kIgnore[] = "ignore";
+
 namespace base {
 class DictionaryValue;
 }
 
 class Chrome;
 class Status;
 class WebDriverLog;
 class WebView;
 
 struct FrameInfo {
@@ skipping 48 matching lines @@
   ScopedVector<WebDriverLog> devtools_logs;
   std::unique_ptr<WebDriverLog> driver_log;
   base::ScopedTempDir temp_dir;
   std::unique_ptr<base::DictionaryValue> capabilities;
   bool auto_reporting_enabled;
   // |command_listeners| should be declared after |chrome|. When the |Session|
   // is destroyed, |command_listeners| should be freed first, since some
   // |CommandListener|s might be |CommandListenerProxy|s that forward to
   // |DevToolsEventListener|s owned by |chrome|.
   ScopedVector<CommandListener> command_listeners;
+  std::string unexpected_alert_behaviour;
 };
 
 Session* GetThreadLocalSession();
 
 void SetThreadLocalSession(std::unique_ptr<Session> session);
 
 #endif  // CHROME_TEST_CHROMEDRIVER_SESSION_H_