Add Android's context menu handler used on the NTP.

chrome/browser/ui/webui/ntp/android/context_menu_handler.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_BROWSER_UI_WEBUI_NTP_ANDROID_CONTEXT_MENU_HANDLER_H_
+#define CHROME_BROWSER_UI_WEBUI_NTP_ANDROID_CONTEXT_MENU_HANDLER_H_
+
+#include "base/memory/weak_ptr.h"
+#include "content/public/browser/web_ui_message_handler.h"
+
+namespace base {
+class ListValue;
+}
+
+// The handler for JavaScript messages related to the context menus.
+// It's the job of the actual HTML page to intercept the contextmenu event,
+// disable it and show its own custom menu.
+class ContextMenuHandler : public content::WebUIMessageHandler {
+ public:
+  ContextMenuHandler();
+  virtual ~ContextMenuHandler();
+
+  // WebUIMessageHandler override and implementation.
+  virtual void RegisterMessages() OVERRIDE;
+
+  // Invoked (by on_item_selected_callback_) when an item has been selected.
+  void OnItemSelected(int item_id);
+
+  // Callback for the "showContextMenu" message.
+  void HandleShowContextMenu(const base::ListValue* args);
+
+  // Below are the message that are so far only triggered by the context menu.
+  // They should be moved to other files if they become used from other places.
+
+  // Callback for the "openInNewTab" message.
+  void HandleOpenInNewTab(const base::ListValue* args);
+
+  // Callback for the "openInIncognitoTab" message.
+  void HandleOpenInIncognitoTab(const base::ListValue* args);
+
+ private:
+  // Used to get a WeakPtr to self on the UI thread.
+  base::WeakPtrFactory<ContextMenuHandler> weak_ptr_factory_;
+
+  DISALLOW_COPY_AND_ASSIGN(ContextMenuHandler);
+};
+
+#endif  // CHROME_BROWSER_UI_WEBUI_NTP_ANDROID_CONTEXT_MENU_HANDLER_H_