Add a way to cancel deferred navigations in NavigationHandle

content/public/browser/navigation_handle.h

 // Copyright 2015 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 CONTENT_PUBLIC_BROWSER_NAVIGATION_HANDLE_H_
 #define CONTENT_PUBLIC_BROWSER_NAVIGATION_HANDLE_H_
 
 #include "content/common/content_export.h"
 #include "content/public/browser/navigation_throttle.h"
 #include "content/public/common/referrer.h"
@@ skipping 75 matching lines @@
   // (distinguished by |IsErrorPage|), and false for errors that leave the user
   // on the previous page.
   virtual bool HasCommitted() = 0;
 
   // Whether the navigation resulted in an error page.
   virtual bool IsErrorPage() = 0;
 
   // Resumes a navigation that was previously deferred by a NavigationThrottle.
   virtual void Resume() = 0;
 
+  // Cancels a navigation that was previously deferred by a NavigationThrottle.
+  // |result| should be equal to NavigationThrottle::CANCEL or
+  // NavigationThrottle::CANCEL_AND_IGNORE.
+  virtual void CancelDeferredNavigation(
+      NavigationThrottle::ThrottleCheckResult result) = 0;
+
   // Testing methods ----------------------------------------------------------
   //
   // The following methods should be used exclusively for writing unit tests.
 
   static scoped_ptr<NavigationHandle> CreateNavigationHandleForTesting(
       const GURL& url,
       RenderFrameHost* render_frame_host);
 
   // Registers a NavigationThrottle for tests. The throttle can
   // modify the request, pause the request or cancel the request. This will
@@ skipping 17 matching lines @@
   virtual NavigationThrottle::ThrottleCheckResult
   CallWillRedirectRequestForTesting(const GURL& new_url,
                                     bool new_method_is_post,
                                     const GURL& new_referrer_url,
                                     bool new_is_external_protocol) = 0;
 };
 
 }  // namespace content
 
 #endif  // CONTENT_PUBLIC_BROWSER_NAVIGATION_HANDLE_H_