Make DownloadHistory observe manager, items

chrome/browser/download/download_service.h

Index: chrome/browser/download/download_service.h
diff --git a/chrome/browser/download/download_service.h b/chrome/browser/download/download_service.h
index 24535f94c7b26fefa47b09160adc17cf2bf85a62..1c72b29105e0a10debdfdcc2dcb634c3cb085ff4 100644
--- a/chrome/browser/download/download_service.h
+++ b/chrome/browser/download/download_service.h
@@ -10,9 +10,11 @@
 #include "base/basictypes.h"
 #include "base/callback_forward.h"
 #include "base/memory/ref_counted.h"
+#include "base/memory/scoped_ptr.h"
 #include "chrome/browser/profiles/profile_keyed_service.h"
 
 class ChromeDownloadManagerDelegate;
+class DownloadHistory;
 class Profile;
 
 namespace content {
@@ -28,6 +30,11 @@ class DownloadService : public ProfileKeyedService {
   // Get the download manager delegate, creating it if it doesn't already exist.
   ChromeDownloadManagerDelegate* GetDownloadManagerDelegate();
 
+  // Get the interface to the history system. Returns NULL if profile is
+  // incognito or if the DownloadManager hasn't been created yet or if there is
+  // no HistoryService for profile.
+  DownloadHistory* GetDownloadHistory();
+
   // Has a download manager been created?
   bool HasCreatedDownloadManager();
 
@@ -56,6 +63,8 @@ class DownloadService : public ProfileKeyedService {
   // callbacks.
   scoped_refptr<ChromeDownloadManagerDelegate> manager_delegate_;
 
+  scoped_ptr<DownloadHistory> download_history_;
+
   DISALLOW_COPY_AND_ASSIGN(DownloadService);
 };