Add Dispatcher class to the Battery Status API module.

public/platform/WebBatteryListener.h

Index: public/platform/WebBatteryListener.h
diff --git a/public/platform/WebBatteryListener.h b/public/platform/WebBatteryListener.h
new file mode 100644
index 0000000000000000000000000000000000000000..b69814adeef7140746471461bbc40e78791d1b5a
--- /dev/null
+++ b/public/platform/WebBatteryListener.h
@@ -0,0 +1,24 @@
+// 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 WebBatteryListener_h
+#define WebBatteryListener_h
+
+#include "WebBatteryStatus.h"
+
+namespace blink {
+
+class WebBatteryStatus;
+
+class WebBatteryListener {
+public:
+    // This method is called when a new battery status is available.
+    virtual void updateBatteryStatus(const WebBatteryStatus&) = 0;
+
+    virtual ~WebBatteryListener() { }
+};
+
+} // namespace blink
+
+#endif // WebBatteryListener_h