Only distill unread items

ios/chrome/browser/reading_list/url_downloader.cc

Index: ios/chrome/browser/reading_list/url_downloader.cc
diff --git a/ios/chrome/browser/reading_list/url_downloader.cc b/ios/chrome/browser/reading_list/url_downloader.cc
index bd69408dc2fecb51e27d8838968c769c52575353..6be56c989c286b1f2e5a9e5c12cab5efa7c59de9 100644
--- a/ios/chrome/browser/reading_list/url_downloader.cc
+++ b/ios/chrome/browser/reading_list/url_downloader.cc
@@ -50,9 +50,7 @@ void URLDownloader::OfflineURLExists(const GURL& url,
 
 void URLDownloader::RemoveOfflineURL(const GURL& url) {
   // Remove all download tasks for this url as it would be pointless work.
-  tasks_.erase(
-      std::remove(tasks_.begin(), tasks_.end(), std::make_pair(DOWNLOAD, url)),
-      tasks_.end());
+  CancelDownloadOfflineURL(url);
   tasks_.push_back(std::make_pair(DELETE, url));
   HandleNextTask();
 }
@@ -65,6 +63,12 @@ void URLDownloader::DownloadOfflineURL(const GURL& url) {
   }
 }
 
+void URLDownloader::CancelDownloadOfflineURL(const GURL& url) {
+  tasks_.erase(
+      std::remove(tasks_.begin(), tasks_.end(), std::make_pair(DOWNLOAD, url)),
+      tasks_.end());
+}
+
 void URLDownloader::DownloadCompletionHandler(const GURL& url,
                                               const std::string& title,
                                               SuccessState success) {