Add new UMA stats to get a handle on Downloads UI Usage

content/browser/download/download_persistent_store_info.h

Index: content/browser/download/download_persistent_store_info.h
diff --git a/content/browser/download/download_persistent_store_info.h b/content/browser/download/download_persistent_store_info.h
index 948d0481d43e83895bf1b9c72991397037196276..8e26ab79771342c80aead03810ffbdf31f9414e8 100644
--- a/content/browser/download/download_persistent_store_info.h
+++ b/content/browser/download/download_persistent_store_info.h
@@ -27,10 +27,12 @@ struct CONTENT_EXPORT DownloadPersistentStoreInfo {
                               const GURL& url,
                               const GURL& referrer,
                               const base::Time& start,
+                              const base::Time& end,
                               int64 received,
                               int64 total,
                               int32 download_state,
-                              int64 handle);
+                              int64 handle,
+                              bool opend);
   ~DownloadPersistentStoreInfo();  // For linux-clang.
 
   // The final path where the download is saved.
@@ -46,6 +48,9 @@ struct CONTENT_EXPORT DownloadPersistentStoreInfo {
   // The time when the download started.
   base::Time start_time;
 
+  // The time when the download completed.
+  base::Time end_time;
+
   // The number of bytes received (so far).
   int64 received_bytes;
 
@@ -57,6 +62,8 @@ struct CONTENT_EXPORT DownloadPersistentStoreInfo {
 
   // The handle of the download in the database.
   int64 db_handle;
+
+  bool opened;
 };
 
 #endif  // CONTENT_BROWSER_DOWNLOAD_DOWNLOAD_PERSISTENT_STORE_INFO_H_