Separate out logic to handle different category/group of context menu items from RVContextMenu class

chrome/browser/tab_contents/menu_category_platform_app.cc

Index: chrome/browser/tab_contents/menu_category_platform_app.cc
diff --git a/chrome/browser/tab_contents/menu_category_platform_app.cc b/chrome/browser/tab_contents/menu_category_platform_app.cc
new file mode 100644
index 0000000000000000000000000000000000000000..910a1d7f68febdcfdebc43d2c093b28d77157436
--- /dev/null
+++ b/chrome/browser/tab_contents/menu_category_platform_app.cc
@@ -0,0 +1,36 @@
+// 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.
+
+#include "chrome/browser/tab_contents/menu_category_platform_app.h"
+
+#include "base/command_line.h"
+#include "chrome/common/chrome_switches.h"
+#include "extensions/common/extension.h"
+#include "extensions/common/manifest.h"
+
+MenuCategoryPlatformApp::MenuCategoryPlatformApp(
+    content::RenderFrameHost* render_frame_host,
+    const content::ContextMenuParams& params)
+    : MenuCategoryBase(render_frame_host, params) {
+}
+
+MenuCategoryPlatformApp::~MenuCategoryPlatformApp() {
+}
+
+bool MenuCategoryPlatformApp::IsCategoryEnabled(int category) {
+  switch (category) {
+    case ITEM_CATEGORY_EDITABLE:
+    case ITEM_CATEGORY_COPY:
+      return MenuCategoryBase::IsCategoryEnabled(category);
+    case ITEM_CATEGORY_CURRENT_EXTENSION:
+      return true;
+    case ITEM_CATEGORY_DEVTOOLS_UNPACKED_EXT:
+      return extensions::Manifest::IsUnpackedLocation(
+                 GetExtension()->location()) ||
+             CommandLine::ForCurrentProcess()->HasSwitch(
+                 switches::kDebugPackedApps);
+    default:
+      return false;
+  }
+}