Add methods to Reading List Model

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 120 matching lines @@
   hasUnseen_ = true;
   if (storageLayer_ && !IsPerformingBatchUpdates()) {
     storageLayer_->SavePersistentUnreadList(unread_);
     storageLayer_->SavePersistentHasUnseen(true);
   }
   for (auto& observer : observers_)
     observer.ReadingListDidApplyChanges(this);
   return *unread_.begin();
 }
 
+void ReadingListModelImpl::MarkUnreadByURL(const GURL& url) {
+  DCHECK(loaded());
+  ReadingListEntry entry(url, std::string());
+  auto result = std::find(read_.begin(), read_.end(), entry);
+  if (result == read_.end())
+    return;
+
+  for (ReadingListModelObserver& observer : observers_) {
+    observer.ReadingListWillMoveEntry(this,
+                                      std::distance(read_.begin(), result));
+  }
+
+  unread_.insert(unread_.begin(), std::move(*result));
+  read_.erase(result);
+
+  if (storageLayer_ && !IsPerformingBatchUpdates()) {
+    storageLayer_->SavePersistentUnreadList(read_);
+    storageLayer_->SavePersistentReadList(unread_);
+  }
+  for (ReadingListModelObserver& observer : observers_) {
+    observer.ReadingListDidApplyChanges(this);
+  }
+}
+
 void ReadingListModelImpl::MarkReadByURL(const GURL& url) {
   DCHECK(loaded());
   ReadingListEntry entry(url, std::string());
   auto result = std::find(unread_.begin(), unread_.end(), entry);
   if (result == unread_.end())
     return;
 
   for (auto& observer : observers_) {
     observer.ReadingListWillMoveEntry(this,
                                       std::distance(unread_.begin(), result));
@@ skipping 115 matching lines @@
 
 void ReadingListModelImpl::EndBatchUpdates() {
   ReadingListModel::EndBatchUpdates();
   if (IsPerformingBatchUpdates() || !storageLayer_) {
     return;
   }
   storageLayer_->SavePersistentUnreadList(unread_);
   storageLayer_->SavePersistentReadList(read_);
   storageLayer_->SavePersistentHasUnseen(hasUnseen_);
 }