Create errors (especially cancellation errors) internally to WebCore, rather

Source/WebKit/chromium/public/WebFrameClient.h

 /*
  * Copyright (C) 2011, 2012 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 123 matching lines @@
 
     // Navigational queries ------------------------------------------------
 
     // The client may choose to alter the navigation policy.  Otherwise,
     // defaultPolicy should just be returned.
     virtual WebNavigationPolicy decidePolicyForNavigation(
         WebFrame*, const WebURLRequest&, WebNavigationType,
         const WebNode& originatingNode,
         WebNavigationPolicy defaultPolicy, bool isRedirect) { return defaultPolicy; }
 
-    // Query if the specified request can be handled.
-    virtual bool canHandleRequest(
-        WebFrame*, const WebURLRequest& request) { return true; }
-
-    // Returns an error corresponding to canHandledRequest() returning false.
-    virtual WebURLError cannotHandleRequestError(
-        WebFrame*, const WebURLRequest& request) { return WebURLError(); }
-
-    // Returns an error corresponding to a user cancellation event.
-    virtual WebURLError cancelledError(
-        WebFrame*, const WebURLRequest& request) { return WebURLError(); }
-
-    // Notify that a URL cannot be handled.
-    virtual void unableToImplementPolicyWithError(
-        WebFrame*, const WebURLError&) { }
-
-
     // Navigational notifications ------------------------------------------
 
     // A form submission has been requested, but the page's submit event handler
     // hasn't yet had a chance to run (and possibly alter/interrupt the submit.)
     virtual void willSendSubmitEvent(WebFrame*, const WebFormElement&) { }
 
     // A form submission is about to occur.
     virtual void willSubmitForm(WebFrame*, const WebFormElement&) { }
 
     // A client-side redirect will occur.  This may correspond to a <META
@@ skipping 272 matching lines @@
     // Extensions3D.h in WebCore/platform/graphics).
     virtual void didLoseWebGLContext(WebFrame*, int) { }
 
 protected:
     ~WebFrameClient() { }
 };
 
 } // namespace WebKit
 
 #endif