Menu hook plumbed through to RequestCoordinator.

chrome/android/java/src/org/chromium/chrome/browser/contextmenu/ContextMenuItemDelegate.java

 // Copyright 2013 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.
 
 package org.chromium.chrome.browser.contextmenu;
 
 import org.chromium.chrome.browser.tab.Tab;
 import org.chromium.content.browser.ContentViewCore;
 import org.chromium.content_public.common.Referrer;
 
@@ skipping 90 matching lines @@
     * @return page url.
     */
     String getPageUrl();
 
     /**
      * Called when a link should be opened in the main Chrome browser.
      * @param linkUrl URL that should be opened.
      * @param pageUrl URL of the current page.
      */
     void onOpenInChrome(String linkUrl, String pageUrl);
+
+    /**
+     * Called to queue a task to sometime later make an offline page for this url.
+     */
+    void onSavePageLater(String linkUrl);
 }