[ChromeDriver] Subscribe PerformanceLogger to CommandListener interface

chrome/test/chromedriver/command_listener_proxy.h

Index: chrome/test/chromedriver/command_listener_proxy.h
diff --git a/chrome/test/chromedriver/command_listener_proxy.h b/chrome/test/chromedriver/command_listener_proxy.h
new file mode 100644
index 0000000000000000000000000000000000000000..5788cae107df18efdc5bd21f9fdca72cc0d9088d
--- /dev/null
+++ b/chrome/test/chromedriver/command_listener_proxy.h
@@ -0,0 +1,30 @@
+// Copyright 2014 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_COMMAND_LISTENER_PROXY_H_
+#define CHROME_TEST_CHROMEDRIVER_COMMAND_LISTENER_PROXY_H_
+
+#include <string>
+
+#include "base/basictypes.h"
+#include "base/compiler_specific.h"
+#include "chrome/test/chromedriver/command_listener.h"
+
+class CommandListenerProxy : public CommandListener {
+ public:
+  virtual ~CommandListenerProxy();
+
+  // |command_listener| must not be null.
+  explicit CommandListenerProxy(CommandListener* command_listener);
+
+  // Forwards commands to |command_listener_|.
+  virtual Status BeforeCommand(const std::string& command_name) OVERRIDE;
+
+ private:
+  CommandListener* const command_listener_;
+
+  DISALLOW_COPY_AND_ASSIGN(CommandListenerProxy);
+};
+
+#endif  // CHROME_TEST_CHROMEDRIVER_COMMAND_LISTENER_PROXY_H_