Last_n: Delete previously saved snapshot when navigating.

chrome/browser/android/offline_pages/recent_tab_helper.h

Index: chrome/browser/android/offline_pages/recent_tab_helper.h
diff --git a/chrome/browser/android/offline_pages/recent_tab_helper.h b/chrome/browser/android/offline_pages/recent_tab_helper.h
index b5472401b6f950036af7fbe5ee1df5eb4f20ef8c..c61fbd7455eb347fcab9f563da99c0bd1d21ccad 100644
--- a/chrome/browser/android/offline_pages/recent_tab_helper.h
+++ b/chrome/browser/android/offline_pages/recent_tab_helper.h
@@ -128,13 +128,18 @@ class RecentTabHelper
   bool downloads_snapshot_on_hold_ = false;
 
   // Snapshot information for the last successful snapshot requested by
-  // downloads. Null if no successful one has ever completed.
+  // downloads. Null if no successful one has ever completed for the current
+  // page.
   std::unique_ptr<SnapshotProgressInfo> downloads_latest_saved_snapshot_info_;
 
   // Snapshot progress information for a last_n triggered request. Null if
   // last_n is not currently capturing the current page.
   std::unique_ptr<SnapshotProgressInfo> last_n_ongoing_snapshot_info_;
 
+  // Snapshot information for the last successful snapshot requested by
+  // last_n. Null if no successful one has ever completed for the current page.
+  std::unique_ptr<SnapshotProgressInfo> last_n_latest_saved_snapshot_info_;
+
   // If empty, the tab does not have AndroidId and can not capture pages.
   std::string tab_id_;