The optional Malware Details also collects HTTP cache information. See design...

chrome/browser/safe_browsing/safe_browsing_service.cc

 // Copyright (c) 2010 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/safe_browsing/safe_browsing_service.h"
 
 #include "base/callback.h"
 #include "base/command_line.h"
 #include "base/lazy_instance.h"
 #include "base/path_service.h"
@@ skipping 1018 matching lines @@
   protocol_manager_->ReportSafeBrowsingHit(malicious_url, page_url,
                                            referrer_url, is_subresource,
                                            threat_type);
 }
 
 // If the user had opted-in to send MalwareDetails, this gets called
 // at the time that the blocking page is going away.
 void SafeBrowsingService::ReportMalwareDetails(
     scoped_refptr<MalwareDetails> details) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
+  details->AddRef();

[lzheng, 2011/03/05 00:37:50]

We should avoid AddRef() and Release(). And I don't think you need the AddRef()
and Release() below. The MalwareDetails uses 'this' in the run(xx), right?

Also, I think we should move the StartCacheCollection() call and its callback to
SafeBrowsingBlockingPage: the malware_details is created there and it is easier
to follow if that class drives this action. So, here SafeBrowsingService only
acts as a proxy to pass the result one. Maybe we could change this API as
acception string only too.

[panayiotis, 2011/03/29 18:14:55]

Done.

+  // Starts gathering data from the HTTP cache, when done, OnReportReady is
+  // called with the serialized report.
+  details->StartCacheCollection(
+      NewCallback(this, &SafeBrowsingService::OnReportReady));
+}
+
+void SafeBrowsingService::OnReportReady(scoped_refptr<MalwareDetails> details) {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
+  details->Release();
+
   scoped_ptr<const std::string> serialized(details->GetSerializedReport());
+
   if (!serialized->empty()) {
     DVLOG(1) << "Sending serialized malware details.";
     protocol_manager_->ReportMalwareDetails(*serialized);
   }
 }
 
 void SafeBrowsingService::CheckDownloadHashOnSBThread(
     SafeBrowsingCheck* check) {
   DCHECK_EQ(MessageLoop::current(), safe_browsing_thread_->message_loop());
   DCHECK(enable_download_protection_);
@@ skipping 94 matching lines @@
   check->is_download = true;
   check->timeout_task =
       NewRunnableMethod(this, &SafeBrowsingService::TimeoutCallback, check);
   checks_.insert(check);
 
   safe_browsing_thread_->message_loop()->PostTask(FROM_HERE, task);
 
   MessageLoop::current()->PostDelayedTask(
       FROM_HERE, check->timeout_task, timeout_ms);
 }