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

chrome/browser/safe_browsing/safe_browsing_service.cc

 // 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.
 
 #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 1048 matching lines @@
 
   DVLOG(1) << "ReportSafeBrowsingHit: " << malicious_url << " " << page_url
            << " " << referrer_url << " " << is_subresource << " "
            << threat_type;
   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) {
+// when the report is ready.
+void SafeBrowsingService::SendSerializedMalwareDetails(
+    const std::string& serialized) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
-  scoped_ptr<const std::string> serialized(details->GetSerializedReport());
-  if (!serialized->empty()) {
+  if (!serialized.empty()) {
     DVLOG(1) << "Sending serialized malware details.";
-    protocol_manager_->ReportMalwareDetails(*serialized);
+    protocol_manager_->ReportMalwareDetails(serialized);
   }
 }
 
 void SafeBrowsingService::CheckDownloadHashOnSBThread(
     SafeBrowsingCheck* check) {
   DCHECK_EQ(MessageLoop::current(), safe_browsing_thread_->message_loop());
   DCHECK(enable_download_protection_);
 
   if (!database_->ContainsDownloadHashPrefix(check->full_hash->prefix)) {
     // Good, we don't have hash for this url prefix.
@@ skipping 91 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);
 }