[HTML Imports] Implement "load" and "error" events.

Source/core/html/HTMLImportsController.h

 /*
  * Copyright (C) 2013 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 24 matching lines @@
 #include "core/html/LinkResource.h"
 #include "core/loader/cache/CachedRawResource.h"
 #include "core/platform/Supplementable.h"
 #include "core/platform/Timer.h"
 #include "wtf/FastAllocBase.h"
 #include "wtf/PassOwnPtr.h"
 #include "wtf/Vector.h"
 
 namespace WebCore {
 
+class FetchRequest;
 class ScriptExecutionContext;
 class ResourceFetcher;
 class HTMLImportLoader;
+class HTMLImportLoaderClient;
 
 class HTMLImportsController : public HTMLImportRoot, public Supplement<ScriptExecutionContext> {
     WTF_MAKE_FAST_ALLOCATED;
 public:
     static void provideTo(Document*);
 
     explicit HTMLImportsController(Document*);
     virtual ~HTMLImportsController();
 
     // HTMLImport
     virtual HTMLImportRoot* root() OVERRIDE;
     virtual HTMLImport* parent() const OVERRIDE;
     virtual Document* document() const OVERRIDE;
     virtual void wasDetachedFromDocument() OVERRIDE;
     virtual void didFinishParsing() OVERRIDE;
     virtual bool isProcessing() const OVERRIDE;
     // HTMLImportRoot
     virtual void importWasDisposed() OVERRIDE;
     virtual HTMLImportsController* toController() { return this; }
 
-    PassRefPtr<HTMLImportLoader> createLoader(HTMLImport* parent, const KURL&, const ResourcePtr<CachedRawResource>&);
+    PassRefPtr<HTMLImportLoader> createLoader(HTMLImport* parent, FetchRequest);
     void showSecurityErrorMessage(const String&);
     PassRefPtr<HTMLImportLoader> findLinkFor(const KURL&) const;
     SecurityOrigin* securityOrigin() const;
     ResourceFetcher* fetcher() const;
 
     void scheduleUnblock();
     void unblockTimerFired(Timer<HTMLImportsController>*);
 
 private:
     void clear();
 
     Document* m_master;
     Timer<HTMLImportsController> m_unblockTimer;
 
     // List of import which has been loaded or being loaded.
     typedef Vector<RefPtr<HTMLImportLoader> > ImportList;
     ImportList m_imports;
 };
 
 } // namespace WebCore
 
 #endif // HTMLImportsController_h