Find reading list entry state in model from url

ios/chrome/browser/reading_list/reading_list_model_impl.cc

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "ios/chrome/browser/reading_list/reading_list_model_impl.h"
 
 #include "ios/chrome/browser/reading_list/reading_list_model_storage.h"
 #include "url/gurl.h"
 
 ReadingListModelImpl::ReadingListModelImpl() : ReadingListModelImpl(NULL) {}
@@ skipping 140 matching lines @@
   unread_.erase(result);
 
   if (storageLayer_ && !IsPerformingBatchUpdates()) {
     storageLayer_->SavePersistentUnreadList(unread_);
     storageLayer_->SavePersistentReadList(read_);
   }
   FOR_EACH_OBSERVER(ReadingListModelObserver, observers_,
                     ReadingListDidApplyChanges(this));
 }
 
+ReadingListModel::EntryState ReadingListModelImpl::EntryStateByURL(
+    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 NOT_PRESENT;
+}
+
 void ReadingListModelImpl::SetEntryTitle(const GURL& url,
                                          const std::string& title) {
   DCHECK(loaded());
   const ReadingListEntry entry(url, std::string());
 
   auto result = std::find(unread_.begin(), unread_.end(), entry);
   if (result != unread_.end()) {
     FOR_EACH_OBSERVER(ReadingListModelObserver, observers_,
                       ReadingListWillUpdateUnreadEntry(
                           this, std::distance(unread_.begin(), result)));
@@ skipping 86 matching lines @@
 
 void ReadingListModelImpl::EndBatchUpdates() {
   ReadingListModel::EndBatchUpdates();
   if (IsPerformingBatchUpdates() || !storageLayer_) {
     return;
   }
   storageLayer_->SavePersistentUnreadList(unread_);
   storageLayer_->SavePersistentReadList(read_);
   storageLayer_->SavePersistentHasUnseen(hasUnseen_);
 }