Implement CSP check for manifest fetching

Source/web/AssociatedURLLoader.cpp

 /*
  * Copyright (C) 2010, 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 297 matching lines @@
 COMPILE_ASSERT_MATCHING_ENUM(WebURLLoaderOptions::ForcePreflight, ForcePreflight);
 COMPILE_ASSERT_MATCHING_ENUM(WebURLLoaderOptions::PreventPreflight, PreventPreflight);
 
 void AssociatedURLLoader::loadSynchronously(const WebURLRequest& request, WebURLResponse& response, WebURLError& error, WebData& data)
 {
     ASSERT(0); // Synchronous loading is not supported.
 }
 
 void AssociatedURLLoader::loadAsynchronously(const WebURLRequest& request, WebURLLoaderClient* client)
 {
+    ASSERT(!m_loader);
     ASSERT(!m_client);
 
     m_client = client;
     ASSERT(m_client);
 
     bool allowLoad = true;
     WebURLRequest newRequest(request);
     if (m_options.untrustedHTTP) {
         WebString method = newRequest.httpMethod();
         allowLoad = isValidHTTPToken(method) && FetchUtils::isUsefulMethod(method);
@@ skipping 20 matching lines @@
         if (webcoreRequest.requestContext() == WebURLRequest::RequestContextUnspecified) {
             // FIXME: We load URLs without setting a TargetType (and therefore a request context) in several
             // places in content/ (P2PPortAllocatorSession::AllocateLegacyRelaySession, for example). Remove
             // this once those places are patched up.
             newRequest.setRequestContext(WebURLRequest::RequestContextInternal);
         }
 
         Document* webcoreDocument = m_frameImpl->frame()->document();
         ASSERT(webcoreDocument);
         m_loader = DocumentThreadableLoader::create(*webcoreDocument, m_clientAdapter.get(), webcoreRequest, options, resourceLoaderOptions);
-    } else {
+    }
+
+    if (!m_loader) {
         // FIXME: return meaningful error codes.
         m_clientAdapter->setDelayedError(ResourceError());
     }
     m_clientAdapter->enableErrorNotifications();
 }
 
 void AssociatedURLLoader::cancel()
 {
     if (m_clientAdapter)
         m_clientAdapter->clearClient();
     if (m_loader)
         m_loader->cancel();
 }
 
 void AssociatedURLLoader::setDefersLoading(bool defersLoading)
 {
     if (m_loader)
         m_loader->setDefersLoading(defersLoading);
 }
 
 } // namespace blink