Const-ify DownloadStatusUpdaterDelegate methods.

content/browser/download/download_status_updater.h

Index: content/browser/download/download_status_updater.h
diff --git a/content/browser/download/download_status_updater.h b/content/browser/download/download_status_updater.h
index 410fa2dec58f9fd433213edd27b6e92f5952f5be..8f5c8e8461bf86100f7d0479904bf6bdf1773c5d 100644
--- a/content/browser/download/download_status_updater.h
+++ b/content/browser/download/download_status_updater.h
@@ -27,11 +27,11 @@ class CONTENT_EXPORT DownloadStatusUpdater
   // If the progress is known (i.e. we know the final size of all downloads),
   // returns true and puts a percentage (in range [0-1]) in |progress|. Also
   // returns the number of current downloads in |download_count|.
-  bool GetProgress(float* progress, int* download_count);
+  bool GetProgress(float* progress, int* download_count) const;
 
  private:
   // Returns the number of downloads that are in progress.
-  int64 GetInProgressDownloadCount();
+  int64 GetInProgressDownloadCount() const;
 
   typedef std::set<DownloadStatusUpdaterDelegate*> DelegateSet;
   DelegateSet delegates_;