Find reading list entry state in model from url

ios/chrome/browser/reading_list/reading_list_model_impl.cc

Index: ios/chrome/browser/reading_list/reading_list_model_impl.cc
diff --git a/ios/chrome/browser/reading_list/reading_list_model_impl.cc b/ios/chrome/browser/reading_list/reading_list_model_impl.cc
index c3e068d65f0249a30a6ce1c36dbd381cdf56d260..a40f45e59334ef562e26e57ac7a9ece519137221 100644
--- a/ios/chrome/browser/reading_list/reading_list_model_impl.cc
+++ b/ios/chrome/browser/reading_list/reading_list_model_impl.cc
@@ -158,6 +158,20 @@ void ReadingListModelImpl::MarkReadByURL(const GURL& url) {
                     ReadingListDidApplyChanges(this));
 }
 
+ReadingListModel::EntryState ReadingListModelImpl::EntryPositionByURL(
+    const GURL& url) {
+  ReadingListEntry entry(url, std::string());
+  auto result = std::find(unread_.begin(), unread_.end(), entry);
+  if (result != unread_.end())
+    return UNREAD;
+
+  result = std::find(read_.begin(), read_.end(), entry);
+  if (result != read_.end())
+    return READ;
+
+  return NOTPRESENT;
+}
+
 void ReadingListModelImpl::SetEntryTitle(const GURL& url,
                                          const std::string& title) {
   DCHECK(loaded());