Wireup SafeBrowsingNavigationObserverManager to help PPAPI download attribution

chrome/browser/safe_browsing/download_protection_service.h

Index: chrome/browser/safe_browsing/download_protection_service.h
diff --git a/chrome/browser/safe_browsing/download_protection_service.h b/chrome/browser/safe_browsing/download_protection_service.h
index 213e2a7443eecf4c0ca144ecd003b68c8b9d7564..e7fee05b4c4adbc2ede1f1289518485c6a5fafc4 100644
--- a/chrome/browser/safe_browsing/download_protection_service.h
+++ b/chrome/browser/safe_browsing/download_protection_service.h
@@ -129,6 +129,8 @@ class DownloadProtectionService {
 
   virtual void CheckPPAPIDownloadRequest(
       const GURL& requestor_url,
+      const GURL& initiating_frame_url,
+      content::WebContents* web_contents,
       const base::FilePath& default_file_path,
       const std::vector<base::FilePath::StringType>& alternate_extensions,
       Profile* profile,
@@ -173,6 +175,11 @@ class DownloadProtectionService {
     return whitelist_sample_rate_;
   }
 
+  scoped_refptr<SafeBrowsingNavigationObserverManager>
+  navigation_observer_manager() {
+    return navigation_observer_manager_;
+  }
+
   static void SetDownloadPingToken(content::DownloadItem* item,
                                    const std::string& token);
 
@@ -296,6 +303,16 @@ class DownloadProtectionService {
     content::WebContents* web_contents,
     ClientDownloadRequest* out_request);
 
+  // If kDownloadAttribution feature is enabled, identify referrer chain of the
+  // PPAPI download based on the frame URL where the download is initiated.
+  // Then add referrer chain info to ClientDownloadRequest proto. This function
+  // also records UMA stats of download attribution result.
+  void AddReferrerChainToPPAPIClientDownloadRequest(
+    const GURL& initiating_frame_url,
+    int tab_id,
+    bool has_user_gesture,
+    ClientDownloadRequest* out_request);
+
   // These pointers may be NULL if SafeBrowsing is disabled.
   scoped_refptr<SafeBrowsingUIManager> ui_manager_;
   scoped_refptr<SafeBrowsingDatabaseManager> database_manager_;