Handle extension webrequest API on the IO thread. This speeds up blocking event

chrome/browser/net/chrome_network_delegate.h

 // Copyright (c) 2011 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 CHROME_BROWSER_NET_CHROME_NETWORK_DELEGATE_H_
 #define CHROME_BROWSER_NET_CHROME_NETWORK_DELEGATE_H_
 #pragma once
 
 #include "base/basictypes.h"
 #include "base/compiler_specific.h"
 #include "base/memory/ref_counted.h"
 #include "chrome/browser/profiles/profile.h"
 #include "net/base/network_delegate.h"
 
 class ExtensionEventRouterForwarder;
+class ExtensionInfoMap;
 template<class T> class PrefMember;
 
 typedef PrefMember<bool> BooleanPrefMember;
 
 // ChromeNetworkDelegate is the central point from within the chrome code to
 // add hooks into the network stack.
 class ChromeNetworkDelegate : public net::NetworkDelegate {
  public:
   // If |profile_id| is the invalid profile, events will be broadcasted to all
   // profiles, otherwise, they will only be sent to the specified profile.
   // |enable_referrers| should be initialized on the UI thread (see below)
   // beforehand. This object's owner is responsible for cleaning it up
   // at shutdown.
   ChromeNetworkDelegate(
       ExtensionEventRouterForwarder* event_router,
+      ExtensionInfoMap* extension_info_map,
       ProfileId profile_id,
       BooleanPrefMember* enable_referrers);
   virtual ~ChromeNetworkDelegate();
 
   // Binds |enable_referrers| to |pref_service| and moves it to the IO thread.
   // This method should be called on the UI thread.
   static void InitializeReferrersEnabled(BooleanPrefMember* enable_referrers,
                                          PrefService* pref_service);
 
  private:
@@ skipping 12 matching lines @@
   virtual void OnResponseStarted(net::URLRequest* request);
   virtual void OnRawBytesRead(const net::URLRequest& request, int bytes_read);
   virtual void OnCompleted(net::URLRequest* request);
   virtual void OnURLRequestDestroyed(net::URLRequest* request);
   virtual void OnHttpTransactionDestroyed(uint64 request_id);
   virtual void OnPACScriptError(int line_number, const string16& error);
 
   scoped_refptr<ExtensionEventRouterForwarder> event_router_;
   const ProfileId profile_id_;
 
+  scoped_refptr<ExtensionInfoMap> extension_info_map_;
+
   // Weak, owned by our owner.
   BooleanPrefMember* enable_referrers_;
 
   DISALLOW_COPY_AND_ASSIGN(ChromeNetworkDelegate);
 };
 
 #endif  // CHROME_BROWSER_NET_CHROME_NETWORK_DELEGATE_H_