Refactor extension event distribution to use Values instead of JSON strings.

chrome/browser/extensions/api/web_request/web_request_api.cc

 // Copyright (c) 2012 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.
 
 #include "chrome/browser/extensions/api/web_request/web_request_api.h"
 
 #include <algorithm>
 
 #include "base/bind.h"
 #include "base/json/json_writer.h"
@@ skipping 899 matching lines @@
 void ExtensionWebRequestEventRouter::ClearPendingCallbacks(
     net::URLRequest* request) {
   blocked_requests_.erase(request->identifier());
 }
 
 bool ExtensionWebRequestEventRouter::DispatchEvent(
     void* profile,
     net::URLRequest* request,
     const std::vector<const EventListener*>& listeners,
     const ListValue& args) {
-  std::string json_args;
-
   // TODO(mpcomplete): Consider consolidating common (extension_id,json_args)
   // pairs into a single message sent to a list of sub_event_names.
   int num_handlers_blocking = 0;
   for (std::vector<const EventListener*>::const_iterator it = listeners.begin();
        it != listeners.end(); ++it) {
     // Filter out the optional keys that this listener didn't request.
     scoped_ptr<ListValue> args_filtered(args.DeepCopy());
     DictionaryValue* dict = NULL;
     CHECK(args_filtered->GetDictionary(0, &dict) && dict);
     if (!((*it)->extra_info_spec & ExtraInfoSpec::REQUEST_HEADERS))
       dict->Remove(keys::kRequestHeadersKey, NULL);
     if (!((*it)->extra_info_spec & ExtraInfoSpec::RESPONSE_HEADERS))
       dict->Remove(keys::kResponseHeadersKey, NULL);
 
-    base::JSONWriter::Write(args_filtered.get(), &json_args);
-
     extensions::EventRouter::DispatchEvent(
         (*it)->ipc_sender.get(), (*it)->extension_id, (*it)->sub_event_name,
-        json_args, GURL(), extensions::EventRouter::USER_GESTURE_UNKNOWN,
+        args_filtered.Pass(), GURL(),
+        extensions::EventRouter::USER_GESTURE_UNKNOWN,
         extensions::EventFilteringInfo());
     if ((*it)->extra_info_spec &
         (ExtraInfoSpec::BLOCKING | ExtraInfoSpec::ASYNC_BLOCKING)) {
       (*it)->blocked_requests.insert(request->identifier());
       ++num_handlers_blocking;
 
       request->SetLoadStateParam(
           l10n_util::GetStringFUTF16(IDS_LOAD_STATE_PARAMETER_EXTENSION,
                                      UTF8ToUTF16((*it)->extension_name)));
     }
@@ skipping 869 matching lines @@
       } else if ((*it)->name().find("AdBlock") != std::string::npos) {
         adblock = true;
       } else {
         other = true;
       }
     }
   }
 
   host->Send(new ExtensionMsg_UsingWebRequestAPI(adblock, adblock_plus, other));
 }