Switch Safe Browsing's metadata from string to struct.

chrome/browser/safe_browsing/ui_manager.h

 // 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.
 //
 // The Safe Browsing service is responsible for downloading anti-phishing and
 // anti-malware tables and checking urls against them.
 
 #ifndef CHROME_BROWSER_SAFE_BROWSING_UI_MANAGER_H_
 #define CHROME_BROWSER_SAFE_BROWSING_UI_MANAGER_H_
 
@@ skipping 59 matching lines @@
     //   other navigation has committed (whether by going back or unrelated
     //   navigations), though a pending navigation is okay.
     content::NavigationEntry* GetNavigationEntryForResource() const;
 
     GURL url;
     GURL original_url;
     std::vector<GURL> redirect_urls;
     bool is_subresource;
     bool is_subframe;
     SBThreatType threat_type;
-    std::string threat_metadata;
+    ThreatMetadata threat_metadata;
     UrlCheckCallback callback;  // This is called back on |callback_thread|.
     scoped_refptr<base::SingleThreadTaskRunner> callback_thread;
     int render_process_host_id;
     int render_frame_id;
     safe_browsing::ThreatSource threat_source;
   };
 
   // Observer class can be used to get notified when a SafeBrowsing hit
   // was found.
   class Observer {
@@ skipping 83 matching lines @@
   scoped_refptr<SafeBrowsingService> sb_service_;
 
   base::ObserverList<Observer> observer_list_;
 
   DISALLOW_COPY_AND_ASSIGN(SafeBrowsingUIManager);
 };
 
 }  // namespace safe_browsing
 
 #endif  // CHROME_BROWSER_SAFE_BROWSING_UI_MANAGER_H_