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chrome/browser/download/download_history.h

Index: chrome/browser/download/download_history.h
===================================================================
--- chrome/browser/download/download_history.h	(revision 86341)
+++ chrome/browser/download/download_history.h	(working copy)
@@ -6,6 +6,8 @@
 #define CHROME_BROWSER_DOWNLOAD_DOWNLOAD_HISTORY_H_
 #pragma once
 
+#include <map>
+
 #include "base/basictypes.h"
 #include "chrome/browser/history/history.h"
 #include "content/browser/cancelable_request.h"
@@ -20,6 +22,8 @@
 // Interacts with the HistoryService on behalf of the download subsystem.
 class DownloadHistory {
  public:
+  typedef Callback2<int32, bool>::Type VisitedBeforeDoneCallback;
+
   // A fake download table ID which represents a download that has started,
   // but is not yet in the table.
   static const int kUninitializedHandle;
@@ -30,6 +34,11 @@
   // Retrieves DownloadCreateInfos saved in the history.
   void Load(HistoryService::DownloadQueryCallback* callback);
 
+  // Checks whether |referrer_url| has been visited before today.
+  void CheckVisitedReferrerBefore(int32 download_id,
+                                  const GURL& referrer_url,
+                                  VisitedBeforeDoneCallback* callback);
+
   // Adds a new entry for a download to the history database.
   void AddEntry(DownloadItem* download_item,
                 HistoryService::DownloadCreateCallback* callback);
@@ -52,6 +61,15 @@
   int64 GetNextFakeDbHandle();
 
  private:
+  typedef std::map<HistoryService::Handle,
+                   std::pair<int32, VisitedBeforeDoneCallback*> >
+      VisitedBeforeRequestsMap;
+
+  void OnGotVisitCountToHost(HistoryService::Handle handle,
+                             bool found_visits,
+                             int count,
+                             base::Time first_visit);
+
   Profile* profile_;
 
   // In case we don't have a valid db_handle, we use |fake_db_handle_| instead.
@@ -62,6 +80,9 @@
 
   CancelableRequestConsumer history_consumer_;
 
+  // The outstanding requests made by CheckVisitedReferrerBefore().
+  VisitedBeforeRequestsMap visited_before_requests_;
+
   DISALLOW_COPY_AND_ASSIGN(DownloadHistory);
 };